That is technically very feasible with RFID on each item associated to a printed receipt with a barcode that can be scanned at the door. The door RFID scanner can build a "manifest" of items observed and compare to the list of items scanned for the receipt. No receipt without payment. Many high value items have the RFID sealed inside the package.
(RFID on each item)
That is the basis for the IBM system that they were promoting in 2007 - I remember being flabbergasted when I saw the commercial on TV
https://youtu.be/wzFhBGKU6HA?feature=shared