[aalleavitch]

I don't think that's so much an adaptive aspect of human societies as it is a result of the sort of memes that are effective at propagating themselves. If you are a meme that is facing selective pressures towards persisting for as long as possible, you'll fare best if you exploit human psychology such that you're very hard to get rid of and invoke behavior in the people that carry you that is oppressively dogmatic and ideally prevents the sort of exploratory behavior that might see you replaced by another meme.