The failed version of this is a QR code that opens a PDF. The guest pinches and zooms, gives up, and asks for a paper menu.
A digital menu earns its place by being current and contextual. It reads the same catalogue the till reads, so it cannot advertise a dish the kitchen has marked unavailable, and it knows from the code itself which table or room it was scanned at.
That context is what makes ordering safe. The room or table is bound from the URL and is the only input trusted — nothing about who is being billed is ever taken from the request body, because the code on the table is a token anybody in the room can photograph.
Staff stay in control. A guest order can require waiter acceptance before it reaches the kitchen, so the floor decides what gets made.