They have no "function" as they are not professionals. The only thing they do is be close to a professional in a personal relationship. Often, if they have a job it does not form a part of this fame. They get invited to the parties which are going to be swarming with media because of their fame, no other reason. If you don't like that - don't go. If you won't want to be photographed half cut and croping someone - don't get drunk.

If they are playing a star, then there is both the aspects of ascendence and fall. Most stars follow both and most stars are happy to have the former and not the latter, but they are both intertwined. If you don't like the package, then don't get involved with it.