I actually wanted to start a thread about this a long time ago, but couldn't figure out how. So I'll just jump in.
One week had Charo sitting in one of the boxes. I don't get why she was on the show that much, but one incident stuck in my head. Tom asks the question, and she gives the answer, followed by "Agree! Agree! Agree!". This was for a win, mind you. Contestant agrees, wins the $1,000, and we go on.
It seems incredibly against the spirit of the game to have the celebrities shaking their heads, shouting advice and doing stuff like that. They're paid to crack a joke, give an answer, and that's it. I never watched the show if Charo was sitting in a box ever again, because that seemed to give the opponent a bum deal.