absolutely. and even more ludicrously, shop managers can refuse to sell items that have been incorrectly priced.
For example at a local shop a sign reading 2 for £1.00 Smarties should have read 2 for 1 Smarties. Which would have put them at 2 for £1.58.
My friend argued until she was purple with the manager and then walked out claiming that she would never return and she would tell her friends and neighbors what had transpired.
All over .58 pence.
You have to check every price in supermarket and price per gram etc. Sometimes bulk items cost a hell of a lot more than the normal price.
Something else that steams me is the constant movement of merchandise, so you cannot find items on your list. It is a ploy to force you to look at and and try other items. I think this is horrible practice especially for customers with disabilities, physical, visual and mental. Like playing tricks.