Manager say read the label and look of the barcode the same is as the item you bought

Hello Peter hope you are all well. I write almost every week a review for picn pay Showgate. But today I must write a BAD rapport regarding them. I went to the shop buy a few items when I back at home I notice the price of the air freshener is different on the slip as the price on the shelves I went back to the store show the manager he went to the selve with me and saw the price change. He said he will pay me the difference but it's the customers responsability to see that the barcode correspond with the item and barcode on the selve I was totally shock in other words a customer must read all the labels not only the price??? I don't think any customer do that they look at the price They don't have scanners for the public at the selves for clients aswell and many items no price on the selve Thank you please I need some feedback regarding this matter ???