I'm guessing they do but having used facebook pixel (and their old cross site ad tracking) myself for business the privacy metadata they vacuum up is usually stuff that is often aggregated 3rd parties where people either passively or actively legally sign away various rights (this is often part of small text that people don't read) to share personal data with various affiliates. This is kind of the dark art of web marketing and Facebook has been one of the biggest beneficiaries of the lack of online privacy laws in the country.