Facebook collects lots of data. They even keep a mood index and studies have used it to predict stock market prices.
Regardless of how many times I advice people I know to watch what they post and reveal, including photos and very private information, they continue to do so thinking it's just paranoia. The sheep are as naive as ever.
Try our govt, foreign govts, police, lawyer, marketers, spammers, identity thieves, stalkers, enemies, co-workers, bosses and even FB themselves.
Did you see the quotes from zukc where he was basically telling his buddy they had all the personal info on every user at Harvard, which means he was basically enabling his buddy to stalk anybody he wanted at Harvard. I'm sure the ladies at Harvard feel really safe after reading that!