Jet cashier removes price tag at till and charges more...

I watched her look at the price tags but the removal of the tag was done so that I did not see. The cashier actually removed a tag with a lower price so discreetly at the counter and charged me the price of another item which was of a different size. Why did she do that???? The price was on the item. I told them to look at the camera to see that the item actually did have a price tag. Stores are worried about customer theft when they should question why an employee is removing tags and doing their own thing. Cashier initials are N. S.