This afternoon I found I'd been short-changed by Tesco on a special offer. It's the second time in a month that's happened - that I've been aware of although there may well have been other occasions.
I bought a couple of packs of herbs on a 2 for £1 offer instead of their normal price of 82p and 79p but the full amount was rung up at the till. I thought the total was more than I expected and checked the receipt. When I took it back I found that I'd been overcharged 61p.
A similar thing happened the other day at Somerfield on a 2 for 1 deal on kitchen towel.
I'm reluctant to conclude it's deliberate - I can't think supermarkets would be so stupid as to consciously swindle their customers. Putting a positive construction on what happened there are so many special offers these days it must be hard to make sure they all get accurately logged onto the system. But had these purchases been part of a larger shop rather than a small one I suspect I wouldn't have noticed. It would be easy enough to slip by.
So I suggest, if you don't already do so, you keep track as far as possible of what you're spending and scrutinise your receipt carefully before you pay or leave the shop.
Do you have a similar experience of being overcharged?