There's something fundamentally appealing about having something you created become part of the social zeitgeist, even if only for a little while. You get a little juice and maybe that turns into bigger opportunities for you. I'm all for that. But because of the way the internet works, it's super easy to take something that isn't your and reappropriate it without even thinking about it. Add to that peoples' misunderstanding of fair use, and you get a perfect storm of ignorance.