".. why did you put it out there for others to see?"I've noticed this argument more often w.r.t FB and other such privacy issues. I think it's flawed.
I joined FB back when it was closed. In my mind I wasn't putting anything 'out there' for the world. The first time they made things public and started messing with the default privacy settings I was worried but gave them the benefit of the doubt. Then the cycle repeated with new features and settings, which were altered from their previous states. From that point on I realised they didn't actually care about privacy the way I understand the term and they've gone on to 'open-up' more and more (rather aggressively in my view). What used to be hidden (or at least you thought it was) essentially becomes public at some point in the future.
Had I known this was the direction FB was taking I would have treated it as a public site from the very beginning. Twitter on the other hand was public from the beginning, so my interactions there have been different. I think it's unreasonable to expect that Joe Bloggs out there can get his head around what's public/private on FB. Even if they do there's no telling what might change in the future.
Of course, I could leave FB but then I'd lose touch with people. So now I leave my profile alone, hardly ever 'like' anything and generally try and limit what I do there. I'm sure FB still gleans plenty of info about me from whatever my friends do (i.e tagging photos, connecting address books etc).