There are God hating atheists. What I refer to are people who were raised within a powerful belief system. Their atheism is powerfully and emotionally reactive against that belief system and it's ultimate symbol. They profess not to believe in that God but much of their own thought system revolves in a negative sense around it.
Edit: Just a note that the specific term "God Hating Atheist" I take from John Gray's book Seven Types of Atheism.