Yeah, even the losers on reality TV shows typically get paid for their time! (The unions might have something to do with that. "Hey, if you're not going to hire actors, you better at least pay your talent the same wages!")These things are not in conflict though.
Just because they don't get a cash prize doesn't mean that they don't get compensated for being on the show.
I'd be surprised if there is ANY show where they can have you appear in episodes as a "cast member" and flat out not pay you at all.