If you want to understand why someone does something, I think they are the best ones to ask. If I wanted to know why a Christian does something, should I ask an atheist? If Emma wants to know why an atheist does something, should she ask you? You seem pretty biased against atheists, reacting in a pretty hostile and inflammitory manner. Just like I wouldn't ask an atheist who thinks Christians are awful and vindictive why they do something, I wouldn't ask a christian who thinks atheists are all bad why some of them are rude. I never said I came here to debate. I came here to talk to Christians of differing views because I study religion. And Emma asked about an attitude problem, not just a spiritual one. Not all atheists are rude or condescending, regardless of their lack of spirituallity.
As far as why an atheist would spend time debating about religion, there is plenty of reason. It isn't as if you decide you don't believe in God and then it never affects you again. Our families are religious, our societies are religious, our governments are religious, and many of these religous people want us to be religious too, or at least adhere to the rules they put in place because of that religion. Would you say an anti-Islam protestor spends his time debating about the religion because he secretly thinks it is true, or that he protests it because the beliefs of Muslims negatively impacts the lives of him and those around him. So it isn't the imaginary thing an atheist is up against. It is those who impose rules based on the belief in the imaginary thing and try to make you believe in the imaginary thing and teach children about the imaginary thing.
Again, I am not here to debate with you. If you ask what I believe, I'll tell you, but I think I have just as much right to offer an opinion as anyone here. Nothing I said to Emma was anti-Christian or inflammitory. I was apologizing on the behalf of rude atheists, and offering possible insight into why they behave that way. I even suggested a method of conversation that would be more likely to get them to accept her views. I know I am a minority here, but I didn't expect such hostility from a Christian just because I am not a Christian myself.