McDonald’s, Meet McPathogens

Of course such a screen would have to be specially made.

Instead you have to pick the burger, then way down on the bottom (where you're not looking because the screens are vertical and huge) there is a button to make it a combo. I never found the combo button on my own and had to ask. You'd think since most people order combos they would make it more intuitive to order those. Finally, there are some combo meals (two cheese burger meal) that you can't get as a combo from the kiosk. You'd have to order single cheese burger combo, customize it, add to order, then select a 2nd cheese burger and customize it-- except you can't because the single patty cheese burger can't be made into a combo meal (the combo button doesn't appear). So then you have to just pick the burger, add fries, drink, etc and presumably pay more. To a human I can just say "number X with ketchup and mayo only" and they have it rung up in seconds where it takes much longer on the kiosk.

The customer still has to manually scan every item. Items have to be placed one-by-one in the bagging area. Any small divergence from this, or something out of the ordinary like an Alcohol purchase triggers an exception and requires human intervention. This is enough automation/tech to be annoying but not enough to solve the real problem.

Contrast that with the Amazon Go store which is automated enough that very few would prefer the cashier route even if available.

5. Once you've learned the idiosyncrasies of the kiosk it is the same on every visit.

Human cashiers vary in their understanding of the menu, the McDonald's system, and the local language. The human cashiers are also just poking their index fingers through a decision tree, though it's broader and less deep than self-serve kiosks often offer us.

If I'm ordering hamburgers for a road-trip I know my wife wants tartar sauce on hers, I want no ketchup on mine but I want extra mustard, and my cousin wants neither.

Trying to convey such a simple order (6Hamburgers)=(2TarterAdded+2(KetchupRemoved+ExtraMustard)+2(no sauce)) is an infuriating exercise in implicit closures.

"So you want extra mustard on the ones without ketchup?"

"On two of the ones without ketchup, yes. Two of the burgers are without any sauce at all."

Try ordering the sandwiches one-by-one and you'll discover that any two identical sandwiches in a row are treated as a mistaken repetition. Etc, etc.

6. The mobile apps allow parallelism. You don't have to wait to get to the counter or even the restaurant to make your order.

While I'm driving my wife can order our food. It's not exactly ready when we arrive but it's a lot sooner than if we'd waited in line.

At Disneyland, we often walked right by dozens of families to pick up our mobile orders because nobody had bothered to understand the app. We saved hours of waiting and given the price we were paying Disney to be in the park that was a huge savings.

The fundamental practical advantages of mobile ordering are so great that the back-end side will never be abandoned. So why not have a giant tablet in the restaurant running the front-end?