The next trade war?

Say you go into a shop to buy a garment. There is no assistant around, so you search the racks yourself, find your size, make sure it fits and then bring it to the checkout. The price tag says €19.95, but you point out to the till operator that you had to do all the work making the purchase, so instead of paying €19.95 you want to pay just €19.

I’m not sure ...