From speedycat2014, Tales From Retail:

Working at the store after Valentine's Day and all of our VD goods were on sale. There is a big sign on the table that says, "75% Off!"

Our store gives refunds if something is mispriced. A woman showed up with her groceries after checking out and had a receipt and heart shaped box in hand. Uh oh.

She was nice, when she asked why her box of candy rang up at 50% off and not 75%. I launched into my usual explanation, ready for the good attitude to disappear. "Actually the sign says UP TO 75% off, candy is only 50%."

She smiled, shook her head and said, "Dammit! Stupid prepositions got me again! Okay, thanks!" And went on her way. That was easy.

--speedycat2014