As promised - here is Peter Harveys 'Meat Eating in early and Theravada Buddhism' from pps. 159-163 of Introduction to Buddhist Ethics, Cambridge University Press. 2000.
"Meat eating in early and Theravada Buddhism
It is often seen as surprising that vegetarianism (Prasad, 1979;Ruegg, 1980) is not more widespread among Buddhists than it is, given Buddhist teachings. In fact, the Buddha's emphasis was on the avoidance of killing. So it is worse to swat a fly - an immediate act of killing - than to eat the carcase of an already dead animal. Only in certain Mahayana texts is vegetarianism advocated. The position in early Buddhism, and Theravada lands, is as follows.
In the Buddha's day, vegetarianism was practised by Jains, though Jains see the vegetables eaten by them as containing a life-principle or soul (jiva). On one occasion, Jains accused the Buddha of knowingly eating an animal that had been specifically killed for him. The donor denied this, and the Buddha explained that a monk may eat meat provided it is 'pure in three respects': if the monk has not seen, heard or suspected that the animal has been killed specifically for him (Vin. 1.237-8). The commentary (on Vin. 111.172) explains that, if a monk has suspicions, because of his having seen or heard of the donors hunting, fishing, or slaughtering an animal recently, he should ask about the meat and can only eat it if the being was not killed in order to feed him (Vin. A. 604-6; Bapat and Hirakawa, 1970:395-6). Elsewhere, the Buddha explains that a monk receives food as a gift from a donor, and his lovingkindness for donors and other creatures is not compromised by such eating, if it is 'blameless' by being 'pure in three respects' (M.1.386-71). He goes on to emphasize, though , that a donor generates much bad karma by killing a being so as to give alms to himself or a monk, through: (1) giving the order to fetch the animal, (2) its pain and distress as it is dragged with the rope around its neck, (3) giving the order to kill the animal, (4) its pain and distress while being killed, (5) the offering of the meat to a monk if it is of a type not allowable for a monk. Here, it can be noted, the evil of the act resides both in the actual actions of the killer and in the suffering of the killed.
Non-allowable food for monks, perhaps offered at times of scarcity, are: the flesh of elephants or horses, as people regarded these animals as royal emblems; dog-flesh and snake-flesh, as people saw them as disgusting; the flesh of lions, tigers, panthers, bears and hyenas, as such animals would smell the eaters and attack them (Vin. 1.219-20). These prohibitions were both to preserve people's faith in the Sangha, which was good for both monks and lay people, and to protect monks from danger, a prudential, not moral, reason.
It is clear from the above that the Buddha would have frequently eaten 'blameless' meat given as alms. Thus the debate (for example Kapleau, 1981) over whether his last meal, literally 'pig-mild' (sukara-maddava; D.11.127), was pork, or truffles dug up by pigs, is rather beside the point. It is notable that the Buddha actually resisted an attempt to make vegetarianism compulsory for monks (Vin. 11.171-2). This was proposed by his cousin, the monk Devadatta, who is portrayed as having been proud and jealous of the Buddha's influence. In order to foment a schism, he proposed to the Buddha that all monks should both be vegetarian and follow a number of previously optional ascetic practices, such as living at the root of a tree. The Buddha refused, reaffirming that the practices were optional and meat was acceptable if it was 'pure in three respects'. Devadatta then attempted to lead his own order, under these rules, seeking to gain support from those who 'esteem austerity'. Elsewhere,such a purely external way of assessing someone's spiritual worth is seen as unreliable. (A.11.71). Prior to his enlightenment, in his ascetic phase, Gotama had himself tried the teachings of those who taught 'purity through food', i.e. living off small amounts of only one type of food, be it jujube, beans, sesame or rice. Such externally orientated practices only made him thin and weak, though (M.1.80-1). The link between vegetarianism and extreme asceticism is also found in another passage, where it is included among the practices of self-tormenting ascetics, along with such things as nakedness, eating once a week, never sitting down, and pulling out hair (M.1.342-3). Such ascetic acts are not seen to 'purify' a person (Sn.249), and meat is not what is to be seen as 'tainted fare' - breaking the precepts is 'tainted fare' (Sn. 242).
It is notable, above, that the Buddha did not even regard vegetarianism as an optional ascetic practice for monks. If they were given flesh-food, and it was 'pure' as described above, to refuse it would deprive the donor of the karmic fruitfulness engendered by giving alms-food. Moreover, it would encourage the monks to pick and choose what food they would eat. Food should be looked on only as a source of sustenance, without preferences. To believe that being a vegetarian is itself spiritually purifying would seem to be an example of the spiritual fetter of 'attachment to virtues and vows'. It is certainly the case that a feeling of moral superiority is a common danger among vegetarians: though it can be avoided! Likewise, vegetarians can in time become disgusted with meat, which can be seen as a form of negative attachment. In any case, as the above suggests, there are many worse actions than eating meat.
The preceding discussion is concerned with what what is acceptable for a monk or nun, who must, with few exceptions, eat what is given to him or her. The considerations for a lay Buddhist are similar, but not identical. A lay person has more control over his or her food supply; ingredients much be directly obtained or bought. Lay people, within the limits of their means, make many preference-directed choices over what they eat. So for a lay person to avoid flesh-food (except, perhaps, when a guest) is not to refuse what someone has graciously offered, and not, as such, more 'picking and choosing' than is normal for a lay person. A lay vegetarian mus, though, be wary of feelings of judgemental moral superiority, and negative attachment to meat. The latter is best dealt with by not refusing meat if one is someone's guest. While it is in some ways more feasible, then, for a lay person to be a vegetarian than a monk, one feature of Buddhism weighs against this leading to vegetarianism being more common among the laity. Normally, higher standards of behaviour are expected of a monk than of a lay person. If even monks are not expected to be vegetarian, a lay person might well think, 'why should I?'
In Theravada countries, vegetarianism is universally admired but little practised.  There is a minority witness of vegetarians, however - such as the one-time governor of Bangkok - and most people have an uneasy conscience when they think about meat eating. Most lay people eat meat, though some abstain on observance days, or during periods of meditation. In Thailand, a few monks let it be known that they would prefer vegetarian food (Bunnag, 1973: 69-70). In Burma, Mahasi Sayadaw recommends vegetarianism as the safest way for monks to ensure that their food is 'pure in three respects' (Mahasi, 1981:45-), and some nuns are vegetarian in periods of more ascetic practice (Kawanami, 1990:27). In Sri Lanka, most nuns are vegetarian (Bartholomeusz, 1994:140), many 'Protestant Buddhists' (see p. 112) have recommended vegetarianism, as does the Sarvodaya Sramadana movement (see pp. 225-34) (Bond, 1988: 280), and some see meat eating as hindering success in meditation (Bond, 1988: 200-4).
In general, it is seen as preferable to eat the meat of an animal which is less intelligent, and/or smaller (cf. p. 52), than the opposite. Thus it is worst of all to eat beef (in Burma prior to British colonization, it was a crime to kill a cow, as it was in the period 1960-2). It is seen as less bad to eat pork, then goat-meat or chicken, and less bad again to eat eggs. Nevertheless, eggs are always regarded as having been fertilized, so to boil or crack an egg is seen as killing a living being (Terweil, 1979:188).
This means that, in Sri Lanka at least, no eggs are used in Buddhist monasteries, and pre-cracked "Buddhist eggs' are sold to the middle-class pious Buddhists. It is seen as least bad to eat fish, an unintelligent form of life that needs little effort to kill. Fish is by far the most common form of flesh eaten, as is reflected in a saying on the abundance of feed in Thailand, 'There are fish in the water, there is rice in the fields.' Nevertheless, the Buddhist ideal rules out even killing fish. This is expressed in one Jataka story, where the Buddha in a past life is said to have been a crane who only ate fish when he found them already dead (J.1.206-8).
It is clearly the case, though, that any lay Buddhist should not kill an animal for food, or tell someone else to do so. Either action clearly breaks the first precept. The question arises, though, whether buying meat from a butcher is participating in wrong action by encouraging it. One passage (A.11.252) says that a person will be reborn in hell if he kills and encourages others to do so. 'Encouraging' alone is not specified as having this effect, but in any case, such encouraging would normally be seen to be of a direct form, for example 'why don't you go hunting?', or ordering a carcase from a butcher (Mahasi, 1981: 46). Clearly, to ask a butcher to kill an animal for one is to break the first precept. In the West, most food animals are killed in large abattoirs, and 'butchers' only sell the meat. Buddhist countries lack such large-scale slaughter-houses (they would be seen as hells on earth), and so obtaining meat is more likely to have the attendant danger of direct involvement in an animal's death. This probably helps to reduce the extent of meat eating.
To make one's living as a butcher, hunter or fisherman clearly comes under the category of 'wrong livelihood' (A.11.208), to be avoided by all sincere Buddhists. Certainly one finds that, in Buddhist societies, butchers (slaughterers and meat salesmen) are usually non-Buddhists, often Muslims (Spiro, 1971:45). By making a living by or from killing, they are seen as depraved people, and are often treated as outcasts. Buddhist fishermen are more common, though they have a low status in society on account of their livelihood. In Sri Lanka, the All Ceylon Buddhist Congress recommended, in 1985, that the government should not support commercial fishing through having a Ministry of Fisheries (Bond, 1988:118). Yet, as fish are seen as a lower form of life than land animals, it is seen as less bad to kill them. The excuse is sometimes mad that they are not killed, but just die when taken out of the water. This is evidently a case of trying to distance oneself from what is recognized as an unwholesome action. In South-east Asia people often catch their own fish, which clearly breaks the first precept; but if a living is not mad from this, it is not seen as 'wrong livelihood'."
---The trouble is that you think you have time---
---It's not what happens to you in life that is important ~ it's what you do with it ---