Atheist chat sight..might go a little bit like this...
''There is no God''
''I agree, there is no God''
''Well I guess that's all we have to talk about''
''Guess so..see ya later''
Actually South Park addressed this surprisingly well. There was an episode where they go into the future to find everyone's an atheist and religion no longer exists. It leads Cartman to ask if no one believes in a god, does it mean all the religion inspired wars have stopped and is there finally world peace? The short answer is no and while atheists all agree that to their knowledge there is no God... that's about the only thing they agree on and wars are still started by all the little things they don't agree on.
So there is obviously more to it than believing in no God, (just like there's more to Christianity than believing in a God), and therefore more to discuss.
I can't help but notice you complain when non-believers mock your faith, yet you handle the personal beliefs of others with over-simplifying and disrespectful ignorance. You don't have to be rude about the fact that you disagree. We may be of different walks of life, but I'd like to hope we can at least agree on "Do unto others..."