Well, in order to fully understand that you have to be a Law expert. But this is basically it: Lucas, who is a "giant", doesn't really care about some stupid site among the other thousands of unofficial Star Wars sites. Also, he has the knowleadge that Mickey Suttle (AKA Shadow) has got some sort of light mental disease, thus he doesn't want to take up a lawsuit against a "retarted" person. I also believe nothing Suttle did goes against the law itself, even being bad stuff. Since he didn't impersonate Lucas to use his money or something like that (he only used him to reply to comments on his website) that's perfectly legal, even being rude. Nothing he did is against the Law, which kinda pisses off someone. Sure it really irritates you, but it's harmless. In other words, a lawsuit against Suttle would be like putting a lawsuit against some kid in school who accidentally hit you with a ball.