It's funny how mcdonalds did everything in their power to make it almost impossible to run their mcdonalds app on a rooted phone, but their backend infrastructure is beyond broken (security wise)
My theory is they store payment information on the mobile app. The app connects to the store wifi automatically, even when going through the drive thru. And processes the payment then. I theorized it so they don’t store credit card info on their servers, simplifying their PCI audits. Presumably they think all that is better than preventing the app from running on rooted phones.