When a person becomes very rich and famous for one specific thing, it is only fair to the rest of society that the person should have to do that specific thing whenever the music comes on. That person got a lot of money for whatever it is they are famous for. They should not hesitate to show it off.
Kevin Bacon is probably constantly harassed by paparazzi and fans. I'm sure he doesn't want to be harassed and bothered at weddings too. He should do whatever he wants and not worry about what other people tell him to do. If he doesn't want to dance at a wedding, he doesn't have to.
As much as everyone would probably love to see Kevin Bacon rock out and do the Footloose dance everytime they see him, I think it's a bit overboard to assume that he should be forced to do it. Sure, it's fun to watch, but I'm sure he has gotten completely tired of hearing people aske him to.
No, Kevin Bacon should not have to dance to Footloose whenever someone turns on the music. Bacon is an individual who happens to have one particularly popular moment in his career, but he is not defined by that moment and has no responsibility to entertain people with a performance on demand. If he is invited to a wedding as a friend or family member, he should be able to go and enjoy himself as another one of the guests.