Did you ever use Konica film?
Once upon a time, Konica made IR film once a year. You had to get up bright and early on the day it came out to get your bricks of 120 for the year. (Slight exageration, but not by much.) I suppose they made one master roll, and then, poof, it would be all gone for the year. Then Ilford came out with SFX200, and they basically gave it up. And now, Konica is gone, along with their color ISO3200 film.
Yes, a run of film can be done once a year. The thing is, the run is part of an on-going film production operation, not "OK, let's start the machine up for a month." I have no idea what goes on inside Fujifilm, but I doubt that it's that dissimilar to Kodak.
The problem is with a master roll not selling in a year. There just aren't enough buyers for the product, and so the film becomes too expensive for the consumer. At what price point does someone stop purchasing the product? A fellow on APUG posted that 35mm Portra was too expensive for him at £6 ($9.30 US). Then what? The product doesn't sell. So at some point, the film still sells, and at another point, it's no longer economical to produce. That's what happened with Kodak, and due to their financial troubles, they decided to drop the whole product line.
I'm guessing that there is a whole staff devoted to each type of emulsion, and the staff has to be kept on standby even if the emulsion isn't being made. Just a guess. So Fujifilm decided to drop an emulsion, along with its attendant staff. I seriously doubt that either Kodak or Fujifilm are doing any research beyond maintaining current emulsion production. After all, Acros 400 120 was dropped because revising the formula wasn't cost effective, i.e., it was predicted to fail its return on investment. And that's for something that was somewhat popular!
Though I'll happily stand up and cry out how much I love film and what it gives me, I do realize that quite soon (2013) there might not be any slide film, and then a bit after that, no LF color film. Kodak is now only doing custom cuttings of 8x10 film in any emulsion, and Kodak is a responsive company. Fujifilm is not known as a responsive company.
One of the things that I wonder about is all of the hoarded film. Somebody posted that they have a 30-year supply in a freezer. OK, how about chemicals to develop that film? I've found a few formulas for E6, so I suppose that Photographer's Formulary will produce a kit once the big guys don't produce it. And film ages, even in deep freeze. So now, unless they've gotten good at developing color without a Jobo, they might be getting Hola results from their hoard. I doubt that there will be commercial processing to meet the demand of a few ultra-long-term hoarders. Such is the future.