"What would I use it for?" It's an honest question. Because most of what Cole's needed, he didn't really need himself. It's things for others, such as fries for the birds and supplies for the carnival. And, well, people wouldn't miss one or two things, little things filched from their noses. It would make Childermass happy.

Any sort of 'buy things because it would make you happy' is a bit foreign to poor Cole. As such, he's downright confused at Reira's suggestion of using his allowance for other things.