Poor customer service

Clicks Harvest Place too 4 Precise Liner had a sticker of R30 at the till when scanned 2 was R30 and another 2 was R100.95 , cashier called supervisor/manager (not sure position) and subtracted 2 from my list .Is not the price you see is the price you pay ???? I tried to say that to them but was is either I take them on price scanned or I leave them and had to leave them so disappointed with clicks .