Are we sure about how this works?
I can understand that, once you sign up for Ultraviolet, that you'll be stuck with it, but what if you never sign up in the first place? I refuse to believe that the studios would release a big movie like Green Lantern that simply won't play at all on any non-networked BD player.
I imagine that, on non-networked BD players, or users without a UV account, the disc would simply be like any other disc. It would play, but you wouldn't get any of the "bonus features" that UV offers.
If they really are going to this "online only" thing, they can all go **** themselves. And they probably will, when they realize that it will result in a 1000% increase in piracy for UV-enabled movies.
Welcome to Rivendell, Mister Anderson.