Before every book fair in elementary school, we were given a little four or five page pamphlet of what paperbacks we could expect to see. It was almost entirely scholastic books, dominated by the popular GOOSEBUMPS, with smatterings of old favorites like BABYSITTER'S CLUB. All of us, little kids with our parent's money in our pockets, flipped through pages, picking out the cool covers and sometimes even stopping to read the blurbs.
Book fairs are designed to socialize kids to do two things: read for fun, and grow into consumerism. I sit at this late hour, some decade and a half later, with an expensive degree in putting words together, as a successful outcome of that project. It worked for us because it was one of our first experiences, outside of juice boxes, to exercise our buying power. Your parents gave you ten dollars and you could buy anything you want - even this book with the scary werewolf on it.
When we were all hyped and ready to spend, we shuffled into the library in a single file line, and were amazed to find that the desks had been rearranged to form a big square, upon which books and book accessories were being sold. Our tiny, one-room library, a shitty public school thing, became a swap meet. It was as exciting as books got at our age.