I have nothing against vegans/vegetarians in general, but I get annoyed by the ones who call meat-eaters "murderers", claim that humans are actually herbivorous and that any animal product was produced by the cruelest methods possible...even when such methods could actually be less efficient than more humane methods.
And I'm especially pissed of by the idea that meat-eaters are basically Human Nazis oppressing Animal Jews.
This type of vegan/vegetarian seems to be highly inclined to appealing to emotion and ignoring scientific facts. Okay, sure, I don't mind if you have a moral objection, and again, I have nothing against vegans/vegetarians in general...but for god's sake, do you have to be a fundie about it?