The world is far bigger than the world humans perceive and, as such, modelled in our very limited minds. And that, in a sense, is what would be consistent to an assertion once made by a commentator on Get Real Post: "I want to grow as a person not only intellectually but morally and spiritually as well, if that requires believing in God then so be it". In that sense, the concept of "God" is a label we put in a thing or a world that is bigger than our persons that we seek to explore and come to terms with.
Some people choose to call the thing or world they seek a "God". And with that, atheists come around and present themselves as the anti-thesis to that approach chosen by some to come to terms with their world. Atheists therefore exist because there is a subset of humanity with a very specific approach to regarding their world.
I noticed that celebrity intellectuals like Richard Dawkins are held up as the posterboys of atheism. But, see, Dawkins is an intellectual and accomplished scientist first before he is an atheist. His being an atheist is but a tiny aspect of his character -- a tiny byproduct of his vast intellect. Ironically, his book The God Delusion had been latched onto as the "bible" of atheism. Uh oh -- bible of atheism. Alarm bells are starting to sound...
Dawkins frames his atheism by his being an evolutionary scientist. Therefore he does not wear it as a fashion label. He wears it more like most of us wear underwear.
Indeed, his follow-up book The Greatest Show on Earth sees him going back to his bread-and-butter: exhibiting to humanity the wondrous beauty of the process of evolution and how it resulted in this "great show" that is life unaided by the designs of some "being".
I'm sure many who see themselves as "atheists" got there in a similar way -- perhaps kind of like how the first Christians became Christians because through a similarly lucid journey (compared to most of us who were simply raised to be such).
The trouble comes when encapsulation sets in on "atheism" much the same way that Christianity had been reduced to a quaint set of rituals and symbols.