Clicks club points

I would just like to know what is the point of having a clicks club card if you lose your points due to incorrect pricing in the store. For example: I took an item from the shelf which is R49.99 when i got to the till it was R51.99. I argued the price with the cashier,so we went back to the shelf and he saw it was priced R49.99.Then he called his supervisor to show her,they corrected it but not with my club points.They redeemed the points with the R51.99 but said they can't take the points from the R49.99.They then said it works like that i lost the points they cant do anything about it. I felt they should have charged me R42.39 with my club points but they made me pay R49.99. So how do this work? The arrogance of the supervisor i could not withstand.