Even though we know it's just a movie, when we see two actors on screen chumming it up, either as friends or as lovers, we automatically think it must be that way in real life too. This phenomenon goes beyond just actors playing roles together.
Anne Hathaway and James Franco have been unanimously described as two of the worst hosts in the history of the Oscars. When Franco was invited to the Howard Stern Show, he started mentioning every negative feeling he had about Anne Hathaway.
Prepare to never believe the movies again as you see which actors couldn't stand being forced to work with their co-stars!