One of the reason that people with faith adopt a label such as Christian, Muslim, Jew and so on, is that a reward is offered to them for wearing the label, collect-able at death. Also there is comfort to be had by believing a benign god is guiding them in their present lives.
Atheists do not believe in a reward or a punishment. I have never seen the need for non believers to adopt a label of any kind. Once we settle upon a lable to wear it becomes necessary to defend that label from becoming tarnished. It also becomes necessary to to close our mind a little in order stay on the 'straight and narrow.'
People who decide to publicly declare themselves as strict Atheists take on all the disadvantages of having a set faith and none of the advantages. To me you either have a faith of you are free. Why should free men wear labels?