What about a concession trailer with a rented commissary? In my county (Blount, TN), at least, you have to have all the necessary equipment, but you can have part of it at a commissary, and that can be any licensed, inspected food establishment, best I can tell. For example, if the commissary has a 3-compartment sink, you don't need one in your trailer, etc. They said food trucks "don't make it?" Does that mean they're not legal, or that they don't stay in business? Never heard of a place where food trucks were illegal.
The Cosmic Pig BBQ
Smokey Joe Silver