Some of those places are great, but the owners can be temperamental.
The California answer, which has already made it to Austin, is food vans where there are few tables, no servers. People wait in line cafeteria style to get their food and take it someplace else to be eaten. It all may be an illusion but I’m generally turned off by such places. My image is seedy greasy food from fly-by-night businesses but there’s no arguing that the low overhead allows for cheaper prices than in a brick-and-mortar restaurant.
When in CA, I’ve seen all kinds of “food trucks” lined up near business areas / buildings, particularly during breakfast and lunch hours. Though I’ve never bought anything from them, I wouldn’t say that the prices are “cheap”, and from what I was told, some of the trucks provide freshly made “gourmet food,” from lobster rolls to specialty burgers or steaks.
Could be that it beats “brown-bagging it” or waiting in line in cafeterias / sandwich shops / Starbucks...
I used to think the same until Franklin BBQ (in Austin TX) opened. IIRC, Aaron Franklin was serving out out of a food truck for several years before he opened his brick and mortar location. His BBQ is some of the best, ever.
Some of those places are great, but the owners can be temperamental.