Some online services are already engaging in price discrimination, though physical retail has greater limitations in communicating prices to individual customers. I think that removing price tags entirely would be necessary for full price discrimination in brick and mortar retail (or some similarly revolutionary step, like AR vision placing price tags on items). That's not to say it's infeasible, but other changes may be necessary first. For example, in an Amazon Go location, you don't need to check out the items at the end. Customers would still definitely want to know prices of items, but I could imagine them caring less about seeing price tags if they aren't checking out immediately after. I think another system that could help would be a partial or full subscription model, where the subscription price could be an opportunity for price discrimination.