IMO, people largely DO care. If you ask the average Joe - is online privacy important to you, the majority would obviously say yes. Why then don't they stop using FaceCrook?

1. The penalty of social ostracism due to the network effect. This is a severe punishment to most humans - particularly in today's socially disconnected world. Without these apps, a large # of people would not have any contact with much of their social circle - including family.

2. Learned helplessness. I think that many people have just given up. Even if they knew how to fight for their privacy, they see time and time again that money always wins.