Lets say I have $200 to buy games for the store. First, how did I come about this $200? Inventory is a zero sum game, meaning I can't buy a new game until I sell an old game. That "old game" sale means I won't be buying it again, as the sales for the item have slowed or I brought in a bunch of them when they were hot and now sales are back to normal. It's a recovered cost from "dead" inventory.
So do I want to spend $200 on the new, hot thing that just came out? Or do I want to buy used games? What are used games? For the most part, they are those games that I just mentioned that I'm not re-ordering. They may be "dead," but they are generally older games with a long tail, meaning their sales potential are extremely limited but have a solid, long term, low level of demand. We get around this by selling them for less money, and thus buying them for less. But do I want to spend my $200 on hot new games or long tail used games? Do I want a quick return on my investment or a slow one?
I don't have a choice. By declaring that I'll be buying used games, I'm obligated to take them when they arrive, whether I can afford it or not. At times I'll say no, such as if we've hit our used game capacity (maybe once a year) or if I'm truly without the funds to buy them, but I almost always take them. That's what it means to be a successful seller of used games. You're always willing to take them in. It's all or nothing or people learn not to bring them. Repeat sellers is the key to used games for me. I don't even know most of the buyers.
So what happens to those used games? Let's say we bought 66 role-playing books for that $200. That's based on our average buy price of about $3. Of those 66 books, perhaps three are somewhat rare or collectible and will go for $15-20 each. These will sit on the shelves for six to eighteen months waiting for their next buyer. About forty of those books will be moderately priced for around $10 and will also sit on the shelf for six to eighteen months waiting for a buyer. The last twenty or so books will never be purchased, ever, no matter what, at any price. They'll find their way into a $1 bucket eventually, possibly given away, or as a last resort carted out to the recycling. If I identify the dud when buying from the customer, I'll try to buy them for less, but it's hard since it requires data on every role playing book ever printed. Oh yeah, and then train staff in that knowledge.
What makes it worth the hassle to do this? With multiple venues to sell used books, such as conventions, auctions and online sales, I can reach a larger audience and drastically increase my likelihood of selling them. When this happens, the economics of the situation are greatly improved. I'm then making far more than keystone (50%) on a sale, and I can often find a buyer for some of those last "20 books." That said, the convention market has tanked over the last two years and there are fewer and fewer buyers. Online venues like eBay rarely sell for more than my original buy price, unless the book is rare.
This means used books often end up in the category where all stores like to hide their disappointments, a merchandising expense. This includes things like mass market games sold at low margins, decorations in the store that happen to be for sale, and other incidentally sellable stuff, like tape measures with your name on them. In the case of role-playing books, the merchandising expense brings in customers from across the region that wouldn't normally visit your store. Some will buy new things too, but most tend to stick exclusively with used games. Despite all this, I still I think it's financially worth the trouble.