There have been plenty of "users" asking "questions" which turn out to be spam and advertising. Some examples include things like "Have The Body You Deserve?" and "Easy Ways to Lose Weight Fast".

EDIT: I have recently found a third example. This nearly confirms my suspicions: "We should view results fast?"

These are blatant advertising, and I suspect that a bot could be to blame. I'm requesting an addition to the account creation process which requires verification that you're human.