What part of Not Killing do you not seem to understand. The comparison to the Government killing is the slippery slope we go on when we say some killing is OK where other is not, such as its OK for our host to kill animals, or the government to kill Afghans, but not ourselves, we have no part of it. What you don't seem to comprehend is not all vegetarians are the same and practice vegetarianism for the same reasons, the Buddha's logic as applied to accepting meat from hosts may work for some vegetarians but certainly not all or even most, in my opinion from a debating sense its really a very poor arguement put forward, kind of like saying if you're not doing any killing and you're in the military, you're not contributing to others killing, when in fact you may be feeding the soldiers or healing their wounds so they can kill more.
The precept is to not kill, and come to an understanding of how you can refrain from killing and contributing to killing, not to make petty little excuses to not take responsibility for your actions and blame someone else for all the killing.
PS I'd like a quote from the scriptures, Dhammanando, where the Buddha says offending ones host is a greater crime than killing a living being. Seems like you've got your priorities backwards, Not Killing is the most important precept of all, and the biggest one in terms of proportion, not offending ones hosts doesn't come into the precepts, if it even comes into the vinaya.......
18 years ago I made one of the most important decisions of my life and entered a local Cambodian Buddhist Temple as a temple boy and, for only 3 weeks, an actual Therevada Buddhist monk. I am not a scholar, great meditator, or authority on Buddhism, but Buddhism is something I love from the Bottom of my heart. It has taught me sobriety, morality, peace, and very importantly that my suffering is optional, and doesn't have to run my life. I hope to give back what little I can to the Buddhist community that has so generously given me so much, sincerely former monk John