how is it not fair use? fair use is not just for select group of people, nor is it narrow at all. I can very well educate people. It is of course for the courts to decide based on the 4 bullet points. But wheres your argument against it?
I don't see how taking the above picture and saying "this is a pinstripe, picture by Deborah" could be dismissed as education, since that is all it is doing, regardless of me selling other animals like it or not. Again it all about how the person uses it, but that's the scenario I thought the op was implying with the question and answer session. Do I think it's ethical? of course not but the law reads that way from everything I've seen.
striping watermarks out and/or claiming ownership is an entirely different scenario, with obviously entirely different intentions, possibly involving fraud.