I tend to take the view that if the law doesn't prevent it, it's ok to do. I don't need legal permission to do something, I just need to avoid things that the law specifically bans.
If someone with a lot of money has a problem with what you're doing, they'll hire lawyers to discover some way that the law prevents you from doing it. If the ensuing lawsuit, which will bankrupt you regardless of its outcome, doesn't serve as a sufficient warning for anyone else who wants to do whatever it was you did, they'll proceed to buy a law that prevents you from doing it.