I don't mind gamification personally. I'll do it to myself, even if it's just the harmless kind of "just keep running until you've reached that tree ... now that tree over there" to keep me going. Gamification works even if you know that it's gamification.

I agree that it brings up ethical issues when you're using gamification for behavior modification of others, but on the other hand it's also a bit like communication (as in "you cannot not communicate", the absence of a signal is a signal as well), when you choose not to gamify something, you're choosing to strengthen the habits that are currently in place.