You know, if nobody cares about this, then why are people constantly up in arms whenever yet-another-Facebook-privacy-scandal surfaces?

Why people object to have e.g. their financial or medical information disclosed?

Yes, there are people who are "sheep" in the sense that they would do anything if there is some voucher or discount for it. But most people would also object to a camera in their bedroom or photos of their kids being posted publicly online for everyone to see.

You are right that most of the stuff is absolutely mundane, especially in isolation. However, with a bit of analysis one could suddenly learn things about you that you would likely want to keep private - e.g. your sexual fetishes, whether or not you have some illness (insurers and some employers would kill for such info!), your political views, ton of data about your interests, which TV shows you are watching, etc. That's an absolute bonanza of data that makes any marketer salivate and see dollar signs. And a gold mine for all sorts of stalkers and creeps too.