Your point is well said and accurate, and was the first thing I thought of as well.

That said, I think we're well past the point of no return vis-a-vis giving Facebook the benefit of the doubt on basically anything privacy-related. I don't know anyone who would argue that Facebook wouldn't do this if they thought they could get away with it; the "Facebook is listening to my conversations and showing me ads" conspiracy theory gained so much traction, not because people want to believe in conspiracy theories, but because people have no difficulty imagining that Facebook would do something like that if they could.