Misleading /Incorrect pricing displayed

I went to Dischem to check the price of honey and ****** drink. They had the 20% off sticker on the shelf. There was a merchandiser (Duncan) close by I called him and asked if the 20% off applies to all customers or loyalty customers only and he confirmed that the sticker I am seeing, the percentage off of it applies to all customers.

I didn't have my wallet at that time, off I went to fetch my wallet from the car and I went back to Dischem, picked 3 packets of 20's. To my surprise after the cashier rang the packets. There was no discount, I then asked the cashier to come see the price sticker only to find that the sale sticker was labeled on wrong products.

I can only imagine how many customers bought these thinking they are saving 20% off only to realise later they didn't really save anything.