I think most internet personas are jerks no matter what genre, the only assholes I consistently meet in person are jazz idiots. Only met a few that didn't talk down to me concerning music.
I agree alot of Jazz musicians are snobs, but their are also alot of nice ones I find. In response to the question about the metal scene, all it is here is a bunch of 15 year olds trying to hard to be metal by buying $150 boots and covering their girlfriends in ugly make up. I listen to metal and I "look" metal, but I would never ever want to become part of a scene.