Bad attitude and Price

Today I went in the store to purchase some items for the house and also paper. The pack of 500 was marked clearly R19.99. The cashier scanned the item and it scanned R 79.99. They called the manager and he inspected. The price i saw was indead it. He then rep**** and said if the barcode on the item correspond he will give it at that price. So please tell me does everyone shop and compare items and barcodes rather than just go to the item see the price and add in into their basket. He laughed while speaking to him. Arrogant AF. IM SURE IF THEY ASK THE STAFF HOW IT IS TO WORK WITH HIM THERE WILL BE A LOT OF COMPLAINS.