I bought Then We Came To The End, a recent novel I liked the sound of but not quite enough to buy it new, and a first edition (Gollancz, 1998) of Nick Hornby's About A Boy.
The customer after me was a tiny boy who had found a book entitled My Dad Can't Dance.
"Is that for you?" asked the shop assistant. Receiving a shy nod, she waved away his money. "I think we can let you have that. I like to see children reading. Do you promise to read it?"
That's how to ensure return visits and donations.