Magic Magnum said
1. That is true, but it does make it far easier to do so. And acts as a way to get loyalty from people you would otherwise not have the loyalty of.
2. That's also true, but it doesn't mean religion doesn't function as a way to worsen/amplify humanity's more violent and barbaric behaviours and tendencies.
1. It depends on the religion. Atheism doesn't state there is a god, but it does mean there's no competition, either. However, in a monotheistic religion, there's a finite number of spots open. Christianity itself actually tends to invert the cult of personality, as they tend to be paranoid about the whole Antichrist thing.
2. You still have to address what people follow INSTEAD of religion, and if following that would be truly better. In the example of Communism, the answer is decidedly not. Sure, religious people have done awful things, too. However, using Bin Laden to make judgements about religion in general is basically the same as using Stalin to make judgements about Atheism. The problem isn't religion itself, it's that there's multiple competing worldviews that can't stand each other. Sure, everyone being Atheists would end most problems associated with religion, but so would everyone being Catholic.
And one more thing: Atheists often claim moral superiority to Theists on the grounds that they don't commit the same crimes they do. Even if we were to assume this is true, that might not be enough. While people do bad things in the name of their religions, they also do lots of good. There's a reason why lots of hospitals are named after saints. Has anyone ever done anything good in the name of there not being a God?