If Nincompoop, Then Infinite Loop, Part 2

Customer: “I need to fill up my truck.”

Me: “Alright, how much gas would you like?”

Customer: “Enough to fill up my truck.”

Me: “Sir, I need to know how much gas you’d like to buy.”

Customer: “Why is this so hard? You tell me how much gas I need, and I give you the money!”

Me: “Each vehicle’s different, sir. How am I supposed to know how much it’ll take to fill up your particular vehicle?”

Customer: “Look at your book!”

Me: “…my book?”

Customer: “Yes, the book! Look up my truck and tell me how much gas to get!”

(My assistant manager comes over to see what all the fuss is about.)

Assistant Manager: “How about you give us $20 for the gas? If you need more, you can come back, and if it’s too much, we’ll refund you.”

Customer: “Aw, forget it. I’ll just circle around the pumps.”

(…which is what he did for several minutes before driving off.)