Atheists: Why are Christians so nice?

I know what you're going to say. "They can be some of the most hateful people ever!", I realize that. Just like you have axe murderer Atheist, you have the Atheist that donates thousands to charity. But it seems like, especially the youth, are SO damn nice. I went to a youth thing at a church I go to, and they are insanely nice to me, much more than non-Christian teens. And I don't understand there ecstatic kindness and optimism. Sure, they've been sold lies, potentially dangerous and immoral lies. But I felt at home with them; is that their deluded means of luring you in, or is there something there?