Price differences

We went to Queenswood Spar in PTA yesterday. We saw a special for Airwick (where you get R20 off), there were about 7 left and under those ones the price said R86.89, when we arrived at the till it was scanned for R96.89. My sister went with the packer to make sure of the price. Apparently they were on the wrong place and the packer quickly moved them to the right place. We decided not to take the Airwick, I told the manager about the situation, she ask us if we checked the barcode. We can't check every item's barcode, especially if we buy a lot of products, we'll be there for hours. We left feeling quite unhappy. When outside we checked our till slip, the batteries we bought were hanging under a flashing price that said R65.99, but we noticed that we paid R114.99. Already knowing what the manager was going to say, we thought it would be pointless to go back and talk to her again. This has happened on previous occasions, it has also happened to my mother, who also buys there. We never complained about the previous ones, we just put the product back, but this was the straw that broke the camel's back.