they have control over giving that information to the 3rd party, but they don't have any control after that, over how the information is used. with that in mind, do you think they have control over their information?
they are choosing to allow a 3rd party access to that information
that's right, allowing that 3rd party. but did they choose to share it with the business partners of that 3rd party too? are they aware of what is happening in the background? even if they didn't just register-accept-next-next-finish it, most people have no idea about it, because there's so little discourse about it.
like, when I registered to facebook many years ago I had no idea what I was doing. I was using their services a lot for years, blissfully unaware that facebook is a shit company. and what control did I have at the end? the illusion of deletion.