If you grow up in a traditional Buddhist community, there's more of a clearly defined set method for being Buddhist, and how to integrate Buddhism into one's life.
If you grow up in a non-Buddhist community, you have to find your own way to a greater degree and its unsurprising that people who have no standardised roadmap within their local community, will come up with diverse ways of applying Buddhism in their own lives. That's neither inherently good nor bad... it simply means there's not much in the way of convention to defer to.
We see these differences even in our interactions on Buddhist forums.
Western Theravada is certainly not homogenous, but neither should it be portrayed as two diametrically opposed approaches.
"Do not force others, including children, by any means whatsoever, to adopt your views, whether by authority, threat, money, propaganda, or even education." - Ven. Thich Nhat Hanh
"The uprooting of identity is seen by the noble ones as pleasurable; but this contradicts what the whole world sees." (Snp 3.12)
"To argue with a person who has renounced the use of reason is like administering medicine to the dead" - Thomas Paine