It has a little serving hatch in the wall, at night the doors are locked so you can't go in yourself, so you go to the hole in the wall and tell the worker what you want and they go off and get it for you. I saw those in Russia of all places (and some other eastern european countries)
I have a petrol station near me that operates like that from 11 pm maybe they just swap the 7--11 sign round to 11-7?