I disagree. People do care about privacy, they just have no way to show it other than to quit facebook and that's something they're not prepared to do.
They'd rather put up with poor privacy controls and keep their account than have no account at all. Just because they're not leaving now, doesn't mean they won't leave when a viable alternative to facebook comes up.
Yeah, I remember telling my increasingly wall-eyed girlfriend about all the data facebook collects and what they do with it and why this means we and everyone we know should switch to the first viable alternative. Her response: "So what? How does it change my life one bit if every company in the world knows exactly what I buy on the internet and what's on my facebook profile? It's not like there are naked or even particularly embarassing pictures there. I just want to see if someone I used to go to school with is fat/a skank/ugly/got religion and then check back in a month or two to see if it's still true. If I can do that, I don't care what Facebook knows about me or who they sell it to."
People care about privacy, but they become complacent in giving it up. Remember the days when people were too scared to put their credit card into an internet website? Things have changed a lot since then, and it's hardly been 10 years.
They'd rather put up with poor privacy controls and keep their account than have no account at all. Just because they're not leaving now, doesn't mean they won't leave when a viable alternative to facebook comes up.