I seriously doubt there's that much detail. It would be dumb for FB to tell customers that something like this is a primary targeting criteria. That's the racket, that FB (probably) doesn't say, and if any customer is asking I can't think that FB would tell them, since it just results in wasting the customer's money.
It's like a conversation I saw last week, that video ads pay out to the provider/site even if the user only sees one second of it before pressing pause or the back-button.
Well the fact that he is a customer already does make it more likely that he will also be a future customer. He already likes XYZ distortion pedals, so lets remind how good XYZ chorus pedals are..
Advertising is such a racket.