Always Right, Even When Ripping Themselves Off

(The store where I work has two deals: a buy three, get the cheapest item free promo, and a 40% off the most expensive item coupon. The customer comes up with three equally priced items and hands me the coupon.)

Me: “Sorry, sir, you can’t combine offers so you’ll only be able to use one promo–buy two, get one free, or the 40% off. You’d save more if you use the buy two, get one free offer so you can keep the coupon for another time.”

Customer: “Well, let me do two transactions then.”

Me: “I could, but then you’d be spending more than you’d need to.”

Customer: “Nooo… I’d get one free and one for 40% off!”

Me: “No, that’s not how it works. See, if you buy these two, you’d get this third item free. So you’d only be paying for two items. However, if you split them up, the “buy two, get one free” offer is no longer valid because you need three items to get one free. So you’d pay for two items and then on your second transaction, you’d be paying for a third item.”

Customer: “Yeah, but it’d be 40% off.”

Me: “Yes, but if you did it in one transaction, you wouldn’t have to pay for a third item at all.”

Customer: “Just let me do two transactions!”

Me: “Okay, okay, sorry, I’ll ring you out now.”