Now, if there are high capital requirements for starting a restaurant, it sounds like there is a market opportunity for someone to make a low-capital way to try out restaurant concepts. That's sort of what has happened with food trucks. In Austin, many storefront restaurants existed as food trucks first. Presumably, they got to see that they were a hit without having to spend a ton up front.
Not really. The main difference is that everything you use is better designed to be easy to clean and hard to break by someone putting in less than minimum effort. For a small business that isn't being lazy to the point of negligence there's really no difference. The same standard of cleanliness is indeed possible in a noncommercial kitchen but beyond a certain scale it's not cost effective. Also, it's not a binary thing. You have tons of hole in the wall restaurants that use a mix of commercial and noncommercial facilities and equipment. Somewhere that serves ice cream will probably have commercial style freezers and mid-high end consumer grade stuff for everything else. You don't need stainless counters to prepare ice cream and you don't need a three bay sink or a commercial dishwasher to clean ice cream scoops. Bars in places where they're forced to serve food by law often only have consumer grade equipment for the preparation of said food.