That is actually a good idea in settings where customers can/want to borrow a device from the store or mall, e.g. the RFID reader can be incorporated into the s

That is actually a good idea in settings where customers can/want to borrow a device from the store or mall, e.g. the RFID reader can be incorporated into the self checkout barcode readers that some supermarkets handout. For a typical mall scenario, though, I think people will be reluctant to deal with the hassle of another device.