I have never understood the appeal of famous people to otherwise mature adults. Outside of the celebrities' profession (films, sports, whatever), they're just people, probably more flawed than most because of the massive adulation they receive.
On the other hand, I think children need people to look up to besides their parents and teachers. A brilliant, talented "idol" can motivate a child to choose a career they might otherwise have not considered.
Because of children, I think famous people do have a responsibility to behave themselves. It's too bad that most don't give a rat's ass about the effect they have on children.
parakeet, of the anonymous-and-likes-it class