Sainsbury's grocery home delivery service has a "Substitution Promise" https://help.sainsburys.co.uk/help/terms-and-conditions/Substitution-promise-T-Cs If they don't have the item you ordered they will choose a substitute. If the substitute costs more they will give you a vou a voucher for the difference. So - If you order 1 bottles of wine at £10 and they substitute it with a bottle of wine at £20 you get a £10 voucher. But - If you order 10 bottles of wine at £10 each, and they substitute them with 6 bottles of wine at £15 each that's not covered i.e. no voucher Sainsbury's see it as a £100 order vs £90 charged. This is despite less items being delivered and a greater cost per item. I'm reminded of Fitz in Cracker at the checkout. "Three bottles of whiskey constitute one item" etc etc Yes you can just refuse the substitution however there is a positive incentive for Sainsbury's to substitute orders with higher value items. The "Substitution Promise" appears misleading and sharp practice in treating multiple items as a single item. I'm planning to see what Trading Standards have to say about it. Any thoughts?