R&S ATHEISTS: Why do you think that even when you tell a religionista with absolutely no equivocation that?

you do not believe in a 'god' or and 'gods', that the religionista will not understand that you really don't believe in a 'god' or in 'gods'? I am endlessly amused by the phenomenon here--that they simply can't imagine that anyone doesn't believe in 'god'. Is it a failure of imagination or a complete detachment from reality?