I would like to nominate a sort-of-self-serve Japanese diner for most brilliant business model.
We had "automats" in the East when I was a kid. The food was in a glass wall with little doors that opened with coins. The Red Spots are a little different.
The Japanese version is 20 seats around a horseshoe counter in 1,000 square feet. You buy food tickets from a vending machine that offers 60 different dishes. Bring the tickets to the counter and one person brings the food, almost immediately, 24 hours a day, while two people work in the back in the kitchen. There is no cashier or cash register, the machine has all the cash in it. (Or credit card payments.)
The average bill seems to be about $5.00. I don't know rents in Red Spot areas but I do know wages. I would guess that weekly costs for rent and staff, generously, at $8,000, food at 40% and revenue conservatively at $24,000 per week.
That is $8,800 a week net, conservatively.