There are lots of atheist assholes. There are lots of theist assholes. I see more atheist assholes online because I talk to atheists more, and the theists I talk to (in the context of the religion debate) are ones I've seen aren't assholes, so it doesn't surprise me that I see more atheist and anti-theist assholes.
"The reason things will never get better is because people keep electing these rich cocksuckers who don't give a shit about you."
-George Carlin
-George Carlin