This is way overblown. How do you see this heist going down exactly?
Someone targets a restaurant, gets QR stickers made, replicates the restaurant ordering system, replaces them on tables, hopes the servers and customers don't notice, people order, somehow the food comes? Or they order from the waiter and then pay, and somehow the bill on the faked site is correct? Then the customer leaves, and the restaurant doesn't even notice and let's this keep happening.
Someone targets a restaurant, gets QR stickers made, replicates the restaurant ordering system, replaces them on tables, hopes the servers and customers don't notice, people order, somehow the food comes? Or they order from the waiter and then pay, and somehow the bill on the faked site is correct? Then the customer leaves, and the restaurant doesn't even notice and let's this keep happening.
Oceans 14 we have your plot right here!