NOT MY RESPONSIBILTY TO CHECK PRICES

I am using this forum as complaining in the store has fallen on deaf ears. I shop at Makro several times in a month and I can say that 9/10 times there is at least one item where the price that scans at the till is not the price on the shelf. I often buy things because they are on special but if the scanned price is incorrect that defeats the object. I get all kinds of excuses. I find it annoying as I now have to try and remember all the prices so that I can check it at the till. I feel that this is not my responsibility and it is unacceptable. How many people actually take note. It is also strange that things never scan for less than the price on the shelf. This is not acceptable and to me qualifies as false advertising/theft