They have a breathtaking modern technical stack at each franchise. They use ai camera tech to measure the "emptiness" of their various pans, which works with historical data and the incoming orders to automatically create store wide alerts about how much and when to add more chicken/etc to be cooked. They pull in tons of sensor data from basically everything in the stores to keep the lines moving, from the tills to door entry sensors to fry baskets, on and on.

Its all run on a small 3 computer cluster that each of 5000 stores gets that is redundant and self healing, and automatically shares data to corporate/etc.

For all the bigotry, its a crazy modern buisness.