It brought me an idea.

For a business that already have many screens for showing queue and pushes their app to order stuff, on-phone controls in-app and a timer set to when food get prepared with some delay can be a banger. Also, gifts for the winners and leaderboards. I don't use them, but it would sure be way funnier than clickers I saw in some of them, especially if people in a queue could just jump into a game at any point, with no start or finish conditions, like in an endless arena shooter deathmatch where you joon, you frag, you log off to your burger. Less waiting anger, more rhytm to the fast-food conveyor, more customer loyalty. Ah, and kids want you to order again to make a rematch.