It's been 20 years since someone showed up at my house and slept on the sofa for a while but in that period visited Sainsbury's and discovered that their implementation of "Buy one get one free" was to remove the price of one object from the total, and the implementation of "Reduced price" was to charge the full price and then remove a chunk and the combination was buy two objects, have both reduced in price, and then deduct the full price of one object
@mjg59 I know someone who worked for Tesco and they had the exact same issue many years ago. I wonder how much software they have in common.
@jmacarthur @mjg59
My partner has also had this exact thing with a UK supermarket staff discount at an employer that was not Tesco or Sainsbury's, so it seems pretty common! In her case the point of sale refused to pay out though and a manager had to come over to void the sale so she could leave paying nothing.