Which supermarkets have you seen doing this? This conspiracy theory about epaper tags changing their price on you falls flat when you think about it for even a moment. The tags do not update fast enough to do that, couldn’t handle multiple people in the same area, and would be impractical to link back to the purchase time, resulting in people noticing the price scanned didn’t match what they saw on the ticket.
Per customer pricing is only possible for online shopping.
Maybe because it is not my first language, but I don't mean they are doing, I am saying they can do it and it is not that difficult.
Pharmacies in my home country are notorious for making personalised prices. Some big brand grocery stores here have "fiddly" cards and face tracking.
They can easily manipulate prices to make you register yourself and then make discount based on some personalisation metric.
We are all used to it though Amzn and others. We just don't realise that all that is needed for it to get to your basket is that one of them to do it and others to follow.
We have seen many recent examples of companies applying abusive corporate practices and instead of capitalising on it, the competitors just follow with some excuse...
Per customer pricing is only possible for online shopping.