The town seems to be as economically isolated as it is in all other ways. The DOD funds Global Dynamics, but otherwise it would appear to be a money-less society: houses and businesses are built and rebuilt, vehicles are upgraded and replaced frequently, tech is freely borrowed and re-purposed, the bank contains technical and personal artifacts. Most notably food from Cafe Diem is explicitly free. Everyone in town seems to have their own niche job with no competition. In fact I don't recall money ever being mentioned other than the government funding GD.
So is the lack of money just an oversimplification of a company town, or there some kind of communal economy in effect? Have the creators ever addressed this?