The fact that villain gives no consideration to raising...
This guy checked, so he's absorbed the flop and might have already decided to snap call any bet. I see all sorts of retarded shit, like villain snap calling a set to showdown on wet boards etc.

I don't think he has a set. I think he has A2ss or 67ss (missed the latter in my range above) but I don't discount sets based on flop snap call because I see sets snap call vs the raiser, even on tt flops.