[_delirium]

It only applies to older users and probably wouldn't explain this case, but Facebook has silently imputed a "like" before, in cases where the user never explicitly liked the page. There used to be a section on your profile where you listed favorite music, books, and films, and at some point a few years ago, they phased that out and did some heuristic processing on what used to be a free-form text field, to convert its contents to the corresponding "likes". That was somewhat annoying, since I hadn't interpreted the act of listing something on my profile as equivalent to a subscription request for that thing's feed.

[kkshin]

This is a valid complaint, although probably has more to do with the fact that someone in product believed this does translate into a like (before the like system existed).

Also I believe Facebook does not show these ads for minors, so most likely she lied about her age... but I remember just vaguely reading about this at some point in the past.

[siegs]

When this took place, they also herded everyone through a "convert your interests to likes" flow so that you had to actually confirm the new likes, rather than just convert it for you.