I listen to a podcast where a couple of the guys went into depth about the new Clippers arena in LA and they’ve really praised the grab and go concessions stuff.
They’ve got a system where you have a profile on a phone app with your a picture of you and it stores your tickets and keeps a card on file for you. Everywhere you go including the team store and concessions have cameras that scan your face and what you’re buying, you don’t pay for anything but instead get sent a bill at the end of the night. Sounds like it’s been a logistical nightmare to work out the kinks early on, lots of refunds for overcharging and lots of people getting away with stuff and normal being charged.
I imagine as time goes on and this technology becomes more optimized and cheaper more arenas/venues are going to be pushing for something similar.