I define the term 'atheist' differently that some people. To me, an 'atheist' is someone who says 'there is no god.' Such a person is, by definition, an arrogant and unreasonable person because such a bold claim cannot be made unless every avenue of investigation has been pursued and the case for theism found bankrupt. That is why the Bible says that only a fool denies the possibility of God or a god. Because of this definition, I think atheists are idiots and few and far between.
Now, there are agnostics that lean toward atheism. But I don't think such people are idiots. I just think they've been misinformed and/or taught a wrong way to evaluate truth. Then there are agnostics who lean toward theism, but remain agnostic b/c of cultural skepticism.
Of course, there are theists who are practical atheists. And there are theists who are worse idiots than atheists. That's another story.