Soda sale price on a quantity count to get the sale. If a customer wants two soda when it's buy 3 or more for x price they only purchase one or two then bitch about it. Same when the 1 liter soda is 8 or more for 0.99 and they bit-ch when they don't buy enough. 

Buy five save five but oops one of the sale items they wanted wasn't part of the sale. They'll bit-ch to no end about it.

Did customers miss the preschool class where you match the correct shape to the correct spot? A lot of customer are idiots when trying to place two matching shapes together.