I agree with the demographics, but I've never understood this connection. With Facebook, the intrusion of privacy happens completely out in the open and you can work with that. By now pretty much everyone concerned knows that they collect and potentially use everything they can. With email interception, on the other hand, that's something you don't have any control over without encryption. So in my mind, I can be a heavy user of Facebook and a heavy user of PGP without any contradiction.