I would still be using Facebook if it was the case where they only have what we give it. But that isn't reality. What Facebook actually does is purchase data f

I would still be using Facebook if it was the case where they only have what we give it. But that isn't reality. What Facebook actually does is purchase data from hundreds, maybe thousands, of other sources and tie that to your account. They follow you around the web with their tracking cookies and save every website that happens to have a Facebook widget. They alter your timeline to conduct psychology experiments. They use other people's data to build a shadow profile of you, even if you don't have a FB Aaccount. For example, building your graph of friends based on the contacts that other people upload. I could go on if I thought harder, but those are just the ones that come to mind first.