I very strongly dislike facebook and can't wait to watch it die, so I know comparing it to a store is a poor comparison. But at the end of the day, fb is a business, and if someone is using fb to try and hurt their business, they have the right to terminate that guy's accounts.
EDIT
My point here is not that we shouldn't point out bad things facebook does simply because it's "just business". I agree that the "they're a business" argument is just a deflection that derails the conversation into some weird business practice discussion, instead of all the bad things fb does.
My point is more that we should try to frame these things so that the headline isn't "facebook banned me". They ban people all the time and not that many people seem to care, and in this case, of course they banned this guy.