Really? You expect every user to understand the extent of FB's reach into their personal information? You expect every user to understand the extent of how companies obtain that data, whether through purchases or covert harvesting? You expect every user to then understand the myriad of ways their data can be used?
We work in tech, but we're quick to forget that most users at best have a simple understanding of, "I mean, they have some of my data, I guess some of the ads match some things I've searched for on Google before." Joe Schmo never reads a ToS, and we can't expect people not involved in this industry to not be surprised when something like this happens.
10 years ago they dismissed people telling them about things like Google Analytics or other external scripts on website. They used the "nothing to hide, nothing to fear" phrase. "You're paranoid no one want simple people's data".
Even better: doing it one week after complaining about how the GDPR and the Right to be Forgotten are bad EU laws.