Snake handling.
First, are you meaning to call Atheism a superstition?
Second, in answer to your question, the guy who said nihilism would be most correct, but not as conceived of by Schopenhauer. Nietzsche's nihilism is a much better fit for this group.
*edit* Nihilism might be tied with making of sandwiches after having received oral sex from your girlfriend. Hmmm...
MasterPudge is just trying to make an anti-religious jab.
And no, superstition is not the right word.