I'm going to go against the flow and say this is a smart move on Stern's part. The fixed costs (R&D) for making this game have already been paid so they are only paying the variable costs (parts + labor) on this one. I am guessing the line is open with a few duds released in a row, and that parts are not available to make in demand games (Jurassic Park Premium) so they have to keep the line running somehow. If you have to fill the line for a few weeks, why not use something that is a sure bet? Even if Stern has a hard time selling these, there is a huge markup on these compared to new games. I'm sure there are lots of people that want an Ironman that only shop for new games. I am willing to bet the majority of Stern buyers are not pinside people, and that the market would absolutely support 200 more Iron Mans, or any other late model Stern. These vaults are a great idea (for Stern) and will help keep the lights on until us pinball nuts can get a Turtles.
Yes Stern could absolutely make a LOTR or Tron vault and they'd be hugely popular with pinball nuts... which is not the majority of the marketplace. I too am hoping for a LOTR, Tron, or TSPP vault someday but can totally see why Stern would go after the low hanging fruit first.