If you are going to do mobile food the real money is in events not setting up on a street.
At one point in my life I was the marketing and operations manager for a sound and power company out of Cleveland. One of the tools I used to find events and the decision makers for events was this site:
https://www.fairsandfestivals.net/states/It's be very useful for a food vendor also. It is what I used when I had my hotdog stand in Florida. If you are familiar with the carnival circuit you know that Gibsonton, Florida is the home of the Showman's Club and the winter home of many carnival vendors. I knew a few of them and they made mad money going on the road for about half the year or so. Of course they had multiple food trailers, mobile bunkhouse for their crews, and land to store, mantian, and repair their equipment, and even house their crews on for the winter.
In short their is big money in mobile food if you do it smart and are willing to spend capital and long hours to enjoy the success that can be had in such a venture. You need a food managers license in most all US states and usually a commissary service on file if you do not own a commercial food storage facility/location.