People care, but assume it's inevitable. The government knows everything about me since I have to pay taxes. Likewise the banks because I have to keep my money somewhere. Likewise my cell provider because I need a phone to participate in society. Social media is not as high on the necessity list, but once you've already accepted this inevitability, how much is going to change if you give up Facebook? There is a downside which is measurable if you value the social contact. The upside is completely abstract and un-measurable. What outcome could you ever point to and say, this thing X happened specifically because I gave up Facebook?