Well, crap is clearly in the eye of the beholder. I've stated before that I'm one of the 16, no, make it 17 fans of the Spelljammer setting.
Clearly not every book is going to appeal to every gamer, but a few books from the larger selection should appeal to every gamer, whether it be setting stuff, player options, monster books, or whatever other flavors that I'm missing. Personally, I've worked on some WotC books (Death Knight template in Monster Manual II, Book of Exalted Deeds, and Serpent Kingdoms), and I've also done quite a bit of work on the Oathbound setting, which is being mentioned quite a bit in this thread - something that brings me great joy!
As a roleplayer and a fan of this particular industry, I have to agree that there are a lot of books out there on the market. I also agree that there is some variation in quality, though most of them meet or exceed my expectations. My personal favorites are Green Ronin, Necromancer Games, Malhavok Press, FFG, and the B5 line from Mongoose. I would mention Bastion Press, but then I'm biased. I don't buy every product from most publishers (the only exception to this being that I have bought every offering to date from Necromancer Games), but instead I pick and choose which ones look the best for my purposes.
I also know that almost all of the books on the shelf are the result of a labor of love on the part of the designers and the publishers. This isn't always the most profitable business to be in, and in many cases the books aren't there to make certain people a whole heap of cash. For most, this is something done in people's spare time, and it is their best outlet for their creativity.
While I agree that there are a lot of products on the market, I don't think I would really want to see fewer of them unless there are fewer books that people feel compelled to write.