1) Compared to other hobbies, the price of books & dice & miniatures are fairly modest. There are people who fix up cars, which is obviously pretty extreme, but even crafty hobbies like knitting have a comperable outlay of costs. Heck, you could collect something-- that is pretty harsh right there.
2) The value of the books is pretty amazing, when you take in to account reuse. Sure, thirty-some bucks is a chunk of change. Of course, that price point gets you an oversize hardcover book, complete with art-- in otherwords, it is pretty reasonable for the physical product. On top of that, these are books that you will re-use time & again-- how often to you look up a rules question, or how a power works, or grab one to entertain yourself in snippits? Because of its nature, the book lends itself to long-term use.
3) Publishing companies are trying to make money, & that isn't a bad thing. You shouldn't get pissed at Wizards of the Coast or White Wolf for coming out with products that you want. That is precisely what you should want them to do! Now, there are arguments that could be made for requiring new products (DnD 4e core rulebooks are less complete as a product than DnD 3e core rulebooks), & that is fine to discuss. Still-- at the end of the day, I want there to be professionally produced gaming products (wedded to fan-produced products) & when they are good & of use to me, I want to buy them.
4) These are small, niche products with narrow demand, produced by small companies (WotC has Hasbro, sure, but that just means that they have a corporate office to answer to). I don't know how to explain this any better: in order to turn a profit, the price points are set where they need to be. Frankly I am impressed the costs of books are where they are, & I am not surprised when smaller, craft presses cost more money.
5) New ideas don't come all at once. Not every product is a trick to screw you out of your hard earned bucks-- sometimes, they are just new. People will sit down & ask "what should we make next?" or hire new talent & suddenly, boom! You've got a whole new direction of things.
I don't know, I'm just musing. I don't by any means buy all output, nor am I saying people can't talk crap about certain moneymaking schemes (DnD Insider, I'm looking at you). It just makes me wonder what people are expecting. I think a certain degree of entitlement is to blame, really. People want what they want, & they want it cheap, cheaper, even cheaper, but higher quality, full colour! Comprehensive-- magically, have everything in it! There have been plenty of scams-- Palladium will repackage its content over & over again-- but real criticism isn't what I'm talking about.