Do you tip the pizza guy?

So last night I ordered pizza. I used a credit card when I placed the order, because I didn't have a fresh 20 dollar bill in my wallet, or any money really. I never carry around money. So I'm signing for my pizza, and the driver is like "anything for the delivery man?"I"m like no thats why I used a card-hence no money idiot. Am I supposed to be like wait a minute let me give you a dreamcast game...geez