Please. Everyone who has their entire life on Facebook put it there voluntarily. You are completely ignoring the people who put and small amount of information on Facebook and retain a large amount of privacy. And despite your not so subtle implication that you are smarter than anyone who disagrees with you, you have completely failed to defend your premise that using Facebook is fundamentally incompatible with privacy.
So your stance is that as a competent, technically savvy person, you are able to maintain your secrecy and/or privacy on Facebook? Are you aware of the vast amount of implicit data they receive just by you logging in and viewing your friend's posts? The amount of resources FB has dedicated to tech like fingerprinting (both browser based and behavioral) is enough to harvest vast amounts of data from even the most technically savvy people such as yourself.