Carruthers, look at it as a gift for people like yourself who can see passed their marketing ploys, you can feel the self satisfaction of not being fooled. Then you can giggle all smug like at the checkout, when you spot shoppers who made the mistake.
This sort of thing has become part of marketing because everyone is trying to live their life on a dead run, no time to read the EULA. We sign contracts with copious fine print, but nobody ever reads it except the lawyers when there's a dispute. LJ can probably tell you how many people buy a car, one of the big commitments in most people's lives, and sign without reading the contracts.
I went into the supermarket and right inside the door was a huge display of berries. They'd set up a stepped like bleacher seating table, covered with fabric, about 12 ft long, with blueberries, blackberries, strawberries, etc. Half a dozen large signs said, "buy one, get one free". Now this wasn't a slapped together display, it had to be designed and planned in detail. Nowhere anywhere near this display was the PRICE. Do you think they forgot? I don't think so. Since I was planning on buying blueberries anyway, I just picked up twice as many, but I'm sure their marketing people think they conned me.
That mini Tesco sounds like what we call convenience stores, WAWA is the local biggie. Park right at the door, grab something you need, pay a premium for the convenience, and on your way. These have become the regular morning on the way to work stop for millions. Coffee, maybe a pack of smokes or a pastry. Sometimes something for lunch if you know you'll be busy at lunch time. When the market has bananas for 49 cents a lb, the WAWA will charge 70 cents for one banana, but in winter you can leave your car running to warm up.