This is depressing, but of even more concern is the fact that this data (and other, perhaps more "important" data) is available to essentially anyone with enough money to pay for it. This obviously includes most governments. I'm fairly sure the data brokers are not too picky about how they get paid.
There has to be regulation at the federal level to stop such practices. Nothing else will do.
Modern programmatic advertising enables each user to be pimped out to whichever manipulator is willing to pay the most. In just a few dozen milliseconds, Facebook will send out your personal data to participants in the advertising system ('bidstream data'), select a winner, and serve their ad to you.
Note: Your data goes out to bidders, and someone pays Facebook for it. That sure sounds like selling your data.
This is not some farcical, imaginary backdoor to collect data and spy on people. It's happening right now. "Patternz", an Israeli spy-tech company, run an advertising service as a front to get free access to bidstream data from 87 ad exchanges and SSPs including Google, Yahoo, MoPub, AdColony, and OpenX.
They take those bidstream data, de-anonymize them, and permanently record them. They claim to have profiles on billions of users including their location history, home address, interests, information about 'people nearby', 'co-workers' and 'family members'.
See also this slide of theirs: https://pbs.twimg.com/media/F-5bA6QW8AAyfSK.jpg, entitled, "We help national security agencies detect audience patterns and user behavior using digital advertising data mining and analytics".
Show us a link to a Facebook advertising API which can give me bidstream data which includes a user's demographic info? The links describe "Modern programmatic advertising" including "Patternz" but have not shown that Facebook is an implementor.
For the record every time I have advertised on both Google and Facebook, it works in reverse: I give them my ad, audience info, and how much I'm willing to bid, and they run an auction per impression (of which I don't get to participate in knowing the details directly). I get no user data, only the bill. If I did get user data (presumably with user consent) I would start my own direct-marketing mailing or email list and stop paying the ad-tech companies each time (who act as gate-keepers).
Only to the extent that I have read earlier reporting about Patternz, and that I have long been aware of the harm and national security risk that RTB poses and shouting about it whenever I can.
There has to be regulation at the federal level to stop such practices. Nothing else will do.