Stars can bring a lot of buzz to movies and all the games, toys and merch that often accompany them. However, it's always a good idea to have your star media trained, especially if he's a little wet behind the ears.
I'm talking of course of Transformer lead Shia LaBeouf bashing games in which he stars. I'm all for honesty, and he may be right about the games not being great to play, but talking down your own revenue steams is never a wise move. They just might dry up.