I think what really bugs me about Facebook in terms of privacy is how practically every part of it pulls out the maximum data possible.
There are fields on the profile for people to put all their personal into. It has a "real name" policy. There were those "like buttons" and such which winded up on countless websites. Tracking pixels for marketing. I'm sure there is more than that.
All that data is then pitched to advertisers as a product.
Also, remember how YouTube used to collect very little data? I don't think it was much more than an email address.
Then, when it got integrated into Google+ one day to try to compete with Facebook, and they demanded the use of Google Accounts, that led to all that data which such accounts require (names, addresses, and so on) being collected as well.
But, they never needed all this data.
