They did put just enough information to be dangerous on Facebook. The girl in this case did the following:
Joined FB and added her details (real name etc) (first mistake)
Added her dad as a friend, even though he objects to her private life (second mistake)
Added the Queer Choir group leader as a friend (third mistake)
So she now has two FB friends with diametrically opposite views, and wants to keep them completely compartmentalised. Trusting Facebook to do that given the beacon fiasco, and the multiple privacy slip-ups since, is not wise. Yes this is FB's fault for having bad defaults, but you can't trust FB to keep all your stuff private, because they really don't care, and have made this clear many many times in the past. Their business model is predicated on sharing your data with as many corporations and people as possible.
There are other ways to share photos and events which are not a ghetto cut off from the web, so it's better just not to join a club which insists all your acquaintances must join in order to share and then lets them know the intimate details of your life automatically.
arguably, the fact that they had a profile on facebook at all means they 'put the information on facebook'. It's a weak argument, imo, but it's being made.
Except that's not correct. If you're on FB then anyone can tag you or put you in a group or any thing else they want. The simple solution is not to use a social networking site if you want to keep your social network private.
Except they didn't. Someone else did.