As some people are just learning, Facebook has been tracking both users and even non-users in a violation of their privacy that most never opted into. Anytime you visit a Facebook related or enabled site, they are tracking you. Conversely as a Facebook user, they track and relate all of your off-Facebook activity on any site that uses Facebook plugins or functionality (which are a lot of sites). This is horrible and should be stopped but in all fairness “they all do it” and if anything Google is probably worse.
If the above is not bad enough, the PRISM network has backdoors to all of these services so you are being violated directly by corporations and multiple governments who index all of your activity. Privacy is a thing of the past unfortunately.
However there are ways to fight back such as disabling cookies and deleting all cookies regularly and especially to use a random VPN to make tracking harder.
It’s not so much that the majority of people have anything to hide, but privacy is a right everyone has. Most people would object to having cameras in the washroom, not because they are doing something wrong but because you have the right to dignity and privacy.
Hopefully the longstanding issue with most giant online sites from Facebook, Google etc.. will drive demands from people around the world to restore privacy and digital rights in an era where infringement is common.