Imagine that each piece of inventory had a per-item unique RFID permanently attached to it. Not just a model unique RFID, unique to that particular instance. Imagine that your phone can read that RFID. Your phone also has an app that can connect to a database, identify the particular product that the RFID represents, and complete a transaction online. Once the transaction is complete, the store's security systems are updated so that that RFID can pass through the entrance scanners without the alarm going off.
Potential pitfalls include the cost of the RFIDs, the ability to detach the RFIDs at any point, the ability to read the RFID on your phone, and alternative entrance / exits of merchandise (e.g. toss through a window).
Potential pitfalls include the cost of the RFIDs, the ability to detach the RFIDs at any point, the ability to read the RFID on your phone, and alternative entrance / exits of merchandise (e.g. toss through a window).
Are there other reasons that this could not work?