Not only that but how many people want LOTR that don't already own one or owned one in the past? And then you get into how many of those can actually afford a premium+ price for a new one. I also don't think many locations want an old looking expensive game when they can get a pro with lcd, better sound, and modern theme for much less.
So far, it seems like the vaults are just low hanging fruit that Stern fills gaps in production to keep workers busy. New art/code is one thing but redoing an entire game and running on a different boardset sounds pretty complicated. Stern would also have to deal with licensing and that could turn into a headache if they want to do new art and code. I don't see the business sense in doing that for a very limited run.