I saw a post on Facebook earlier this week saying how great the world would be if only bookstores had shopping carts....
The used bookstore where I worked when I was in high school had shopping carts and Ida's customers used those carts. It wasn't some wishful hypothetical situation -- those ladies would leave the store with big paper grocery bags full to the brim with books and they'd read them all and bring them back to trade for more.
On Saturdays, the counter was piled up to our eyes with books that had just been traded in. We'd add up their value on little notepads, no calculators allowed. (Until recently, I'd forgotten all about that little skill. When it comes to useful math, I know what I'm doing -- or did thirty some years ago!)
I miss those days.