[jcnnghm]

In retrospect, I think this is the result of Facebook transitioning from a "private" social network to a public network, when they decided to accept anyone over the age of 13. When Facebook was college-only, I think one of the major appeals was the ability to widely share information, with the one restriction being that it was kept to your peer group. I think there is a whole host of things that young people are willing to share openly with their peers that they also don't want to share with their parents or other authority figures. Further, in many cases, that desire for privacy is not misguided; protecting controversial beliefs from people that have power over you is actually kind of wise.