Atheists often criticize religion, so a perception develops that atheism must be anti-religious - but this is not quite true. Atheism is just the absence of beliefs in gods and can thus occur inside or outside the context of religion. Thus, an atheist might be devoutly religious, devoutly anti-religious, or completely apathetic with regards to religion - exactly as with theists. It all depends on the individual and what ideas, beliefs, or principles they have aside from atheism.
Read Article: Myth: Atheism is Anti-Religion, All Atheists Hate Religion, Say Religion's Evil