Many baked goods are much better when they still have their cooking warmth. Some foods, like pizza, are nearly always served this way, but others are only done this way occasionally. Several companies have used this to offer a much tastier product than you'd normally get:
Midwest Airlines chocolate chip cookies, which they would bake fresh on-board. Good for a cookie, let alone an airline cookie.
Bertucci's rolls, a somewhat typical roll that is famously delicious because it's served just out of the oven.
Krispy Kreme doughnuts, with a "hot now" light so people know when they can get them right out of the fryer.
Some of this is that in cases where it's not that hard to serve it fresh it's unexceptional to serve it that way. You wouldn't normally eat waffles, pancakes, crepes, popovers, or pasta except completely fresh. Thinking about why we do these this way, I think it's that they're operationally simple: short cooking times and small minimum batch sizes. Bertucci's and Midwest handle this by serving the same product to everyone, which really only works if you make it a central aspect of your identity.
If we could sort out the operational aspects of timing and preparation, it seems like we could be generally eating a lot tastier food. Burgers on fresh-baked buns, etc. Improvements here could be well-received!
In my experience, cafeterias are more likely trying to be inoffensive to everybody than to be trying to reduce costs, and in any case their costs per person are lower than the per-person costs of preparing comparable food at most, if not all, qualities of food.
The line between cafeteria and buffet restaurant isn't perfectly defined, and I think that there are already businesses that operate on a cash-per-eater basis that are substantially high-end cafeterias. Shifting to a pay-per-month basis for them seems plausible, but I'm not sure if they get the price per day down to commercially viable levels without sacrificing quality.
I think a tech office cafeteria is going to have a disadvantage in that it is going to provide mostly one real meal per day while also being required to provide snacks and beverages throughout the day, but it might have sufficient funding to be an interesting example.
To test the concept properly I'd want to have a cafeteria located near (within a short walk during lunch break) some (tech?) office buildings that offered monthly memberships as well as daily sales. A company-owned cafeteria for employee use is going to have illegible, although likely higher, value/cost.