(2445;40215)
The question is not, "If God didn't exist, would you continue to practice?" The question is, "If you stopped believing in God, would you continue to practice?" So unless you believe the world would come to an end the second you stopped believing in him, the answer "I wouldn't exist" is just dodging the question.
I get the feeling this is one of those atheistic jabs again, but I'll play along. If I stopped believing in God, of course I would stop practicing going to church, praying, etc.. That is because if I believed in Him, that would be the intrinsic definition of "practicing", as true Christians believe that faith manifests itself as those types of works (or practices). So if I stopped believing and yet practiced, that would be the same as not believing and believing at the same time: a severe logical fallacy.