Well if you have nothing to hide then why worry? This is what you tell the people when you try to violate their rights in an illegal search.
Consider this. You or your children, with an expectation of privacy, post a bunch of pics from a frat house party. Then you put up a few shots of illegal drugs being used….;followed by some off color political comments. All of this is intended for your friends to get a laugh. And you have nothing to hide………..Until you or your children go to apply for a job or a security clearance and some employer insists, as part of the hire process…that you open your page and let them inspect your fun.
Likewise I have been able to find friends I had lost track of. Great way to find old pals! BUT….what if I had just been arrested and I wanted to have a chat with various witnesses and their children. OR I just wanted to visit folks houses when they were out of town. All that stuff is on Facebook pages.
You gotta consider what you post and who will eventually view it.
Or why do iy?