When men watch celebrities, with whom are they most interested in? Tom Cruise, Brad Pitt, perhaps David Beckham? Who ever it is that men tend to watch, they too go to their barbers and ask for specific celebrity hairstyles. The difference between men and women is that they don't necessarily tell each other that their hair is styled after a particular celebrity.
The tendency to stick with particular celebrity hairstyles is prevalent with celebrities as well as with other men. Because of this, men also tend to keep a specific barber for most of their lives, where women tend to bounce from hairdresser to hairdresser as the mood for something new strikes them.