Hussar
Legend
/snip
I wonder what proportion of game books are actually sold to people who play the game regularly and make real use of that book when doing so? It's probably shockingly low.
I think that the second part there, "make real use of that book" is where you're going to find a vanishingly small percentage of any given book use outside of core. Makes sense really. How often do you use a given module? Once? Twice? For maybe eight to ten weeks. Then it sits on your shelf for the rest of the time. And that's for a module which is meant to be used heavily in play. Books like the Complete X or, even smaller niche like the Environmental books in 3e are even less used. It was that realization when the 3e to 3.5 switch happened caused me to seriously curtail my RPG book budget. I had a fair decent 3e collection. My 3.5 collection is significantly smaller and my 4e actual physical book collection consists of the core three only. Plus a DDI account.