Well so long as we're all clear on what you meant we can move on. It's not true that atheists are incapable of being moral, certainly, and it's ad that some people think like that. The evidence also is that for the most part some people are just nasty and religion doesn't always do much, if anything, to change that.
Neither side can really claim to have the moral high ground overall. There was a famous debate between Tony Blair and the late Christopher Hitchens about this, "Religion can be a force for Good in the World", when Blair's (supporting the motion) argument seemed to be that, well, some religious people are good people, and Hitchens's counter-argument, never really satisfactorily answered, was "but you don't have to be religious to be a good person".
Religion can be a force for good in the World, and usually is on balance, but has also been yet another clock nasty people can hide behind. To dislike and persecute other, different groups; to subjugate the masses; and to provide them yet another way to more money and power.
Despite all of that bad stuff, Religion has been a force for good. For a time, it drove developments in Science, Art, Literature and Music. Many people have been motivated by religion to set up charities. Maybe they didn't need to be, but they were. Religion can provide a sense of community and togetherness -- at the moment atheism doesn't really do that, because it's mainly just a set of people spread all over the place whose main feature in common is what they don't believe in rather than what they do. Sadly, many people in the world do need a motivation to be good. Sadly, even with that motivation, many are not good. And, sadly, that motivation often seems to have to be a (what I believe to be) false view of the World.
In time I believe this will change, because all of the motivating factors that Religion provides to drive charity -- community, primarily -- can be provided without invoking the existence of God. At the moment it might just be a weird phase we are going through, when the World slowly moves away from Religion but hasn't quite decided what it is moving towards.