I don't think many people are so concerned about the privacy features on their social network. Social networks to some degree are inherently about making private things public. A lot of the backlash Facebook gets from the average person is about their political moderation.

At some point the public has been informed that Facebook uses their data to advertise, and apparently that cost is worth it to them for the products they give. So far no one has really found a good paid model for social networks, and ads that use data are way more profitable, so here we are. Companies aren't a charity, they gotta make money somehow.