Just started working in a famous fast food chain restaurant, where I USED to say they could automate the place and get rid of the employees.
But that was before I started working there and found out just how much goes on in the back to make sure you can get your double burger for a dollar. Namely, a LOT of cleaning. Pans, racks, bins, tools, huge cooker parts. All of it is greasy and gets filthy and has to be cleaned all the time. Putting in a robot to make burgers might be easy but who is going to pull out the grease bin and carefully dump it? Who is going to clean all the other grill parts and other crap?
Seriously, probably 70% of the effort spent on any food item is in the prep and clean before and after. Cooking and assembling the food is a small part.
They will have totally re engineer the restaurant to accommodate automated production. Every single part will need to be redesigned and tested. And it may still happen but not any time soon.