As a consumer, I vote with my wallet. I don't have time to waste re-working rules and such. I need the product to be inspired and fully functional.
As a merchant, I push people toward great products (and not just stuff that I have on my shelf). Sometimes, the customer will still get what they came looking for, but many times, they go away with a great book that they thank me for later.
One could say that customers are stupid, but I think that is not the case (and I'm not just being politically correct either). Customers are apathetic and go to the game store to find products that are being sold to other gamers in their town. The store help and customer service is lacking, so there is no guideance there either. I used to be this way before I started my own shop. I would go into the FLGS and wander, WANTING DESPERATELY to spend my money and get something to read that I would enjoy. I got tired of trying to spend my money, preferring to hold on to it versus wasting it on 64 pages of disappointment.
The store owners (or the people that do the ordering) are the stupid ones. They may only stock the bigger names or the bigger product lines because they perceive that they'll have better sales from them versus the smaller (IMHO, higher quality) publishers. The full color glossies and marketing they get through the distributors has much to do with that. The distributors pass out lots of the higher volume crap to spur sales because they have a better margin from those publishers than the smaller ones. This really stacks the supposed ballot box when the options to the consumer are limited.
As for publishers doing the same thing over and over, this is true for some books like the Dwarves example. I've also been screaming for a much better alternative "Oriental Adventures" book for a long time (non-Rokugan primer). While there might be some inspired "re-tread" on some of the same old topics, there are MANY areas that have not been fully explored.
This supposed "d20 market shrink" I think has more to do with stiff competition by smaller, "hungrier" companies digging into the sales of the larger publishers. If anything, my sales have been going up and I'm selling more of the smaller publishers than ever before. Of course, since I prefer smaller publishers and steer my customers that way, that may have something to do with it too.
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