Except for when they do it without you even knowing your sending information to them. If you haven't heard of shadow profiles, then now is the time to learn about them.
And don't get me wrong, I understand that I can do stuff to stop these things, but I don't see why I should have to, quite frankly.
The point is that even if I have never visited Facebook, they more than likely know a lot about me already, unless explicitly going out of my way to stop it.
