Absolutely. I have two further points:
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?