An Unexpected (And Possibly Rude) Request

While I was handing cash to the gas station attendant at Raceway, he made a strange request . . . he said, "Do you have any extra?" and I was confused-- it was very early in the morning-- until I saw that he was looking into the back of my Jeep, where I still had a bag of soccer balls from the fall season, and it took me a second to realize he was asking if I could spare a ball for him, because obviously I had too many balls for one man (despite the fact that a cheap soccer ball costs one quarter the price of a tank of gas) and once I understood his request, I answered: "They're not mine, they're the school's soccer balls," and this seemed to satisfy him . . . but I think this a breach of etiquette . . . when you are paying money for something, the person you are paying shouldn't ask you for some of your stuff, right?