But also, letting me pay and leave without having to catch the eye of an overworked, underpaid waiter, mime paying and wait for the one card-reader to become av

But also, letting me pay and leave without having to catch the eye of an overworked, underpaid waiter, mime paying and wait for the one card-reader to become available is golden. Why not both? Online ordering via table-unique QR if you want it, otherwise wait for service. They're all going through the same system so you can mix and match.