Indeed, URD way of doing things seems to be much cleaner. The biggest work resides in doing 3D models and physics. Creating official skins and using real names is in comparison much less work and compromises legality of selling it. It would have been wiser to sell a mod with fake names and skins. A free anonymous update for it, providing the real team names and skins which would yield the same results avoiding problems. Now, as you say, while stealing others project is morally shitty, legally he could be in less trouble.