Are we being cheated?

This is one of a few times that this has happened when I do my weekly grocery shop PnP.<br> <br> I'm prepared with my list and calculator, adding up the price of items as I go along to make sure I don't go over budget. And yet there are a few too many time when everything has been scanned through the till, the total sum is higher than my calculation. I did wonder if i was not checking the price tag carefully against the product I wanted, so the next time I started paying more attention. But no matter how careful I am, the total is always higher. Staring to think there is a bit of nonsense going on here? Why are the prices on the shelf not the same as the bar code being scanned? How is this going to be sorted out? I'm feeling rather **********!!