Yet another experience just now of the discounted price advertised on the shelf not appearing when I scanned the item. The discount was £10, so I wasn't prepared to just write it off.
The first assistant was struggling to understand the problem and although I said it was the top item of the list on the screen he was examining a different product. When I clarified which product it was he started scrutinising the packaging as if the discount would somehow be printed on the box.
I said I would go to the shelf to take a picture of the ticket which showed the reduction. At this point a second assistant appeared and came with me to the aisle whereupon she took the ticket out of its holder. She then told me the product I was trying to purchase was different to the one the ticket referred to because the item I had was 50ml whereas the ticket said the product was "£40 per 100ml".
I tried to explain that this didn't necessarily mean that the product was 100ml, it was just the cost per 100ml, but I couldn't really get her to understand. She wandered off with the item, I waited a few minutes and then asked the other assistant to remove it from the self-service till, paid for the rest of my shopping, packed my bag and left, by which time there was still no sign of the second shop assistant.
Surely someone who works in a supermarket has come across the concept of price per weight/volume? I mean it's displayed on the shelf for just about every product in the entire store! Or did I expect too much?