Creepy because that's an lot of information facebook lets you look up about people pretty easily using their api. Not necessarily objecting but it is a little creepy when you think about it.
People might also have an unreasonable expectation that there's some law against misusing their data. Partly, it's because that is true in some areas, e.g. the phone company can't run speech-to-text on all your conversations and sell histograms of your word usage, so people might assume Facebook can't either.