I have seen, and voted on, quite a few questions that are and indeed should be closed as NARQ, despite having answers. I can't see why it having answers should make any difference. For the particular question you linked I admit I don't see why it was closed as NARQ but the fact that it does have an answer still makes no difference.
I think you're forgetting that there is a huge difference between not a real question in absolute terms compared to not a real question within the context of the site FAQ.