If I might add a word here . . .
Most people resent what lawyers charge but have no choice if they are in need. They'll pay top-dollar for top advice in order to keep their butts out of court. They will buy high-priced plumbing fixtures instead of Home Depot specials in order to boost the value of their home (or their own cachet within their social circle). Jewelry is strictly a luxury and follows the same rules as exotic plumbing fixtures, fancy cars, and designer shoes.
Books are in a different category. Books are available from libraries. Books are purchased once and then borrowed by friends. People don't necessarily see books as a necessity, though the information contained in them might be. The internet has put a dent in many people's desire to buy non-fiction books as most of the pertinent information is available there for free.
I say this as a book addict who once belonged to so many book clubs I finally had to go cold turkey or risk losing my aparment because I was falling behind on the rent. If anyone's going to buy a high-ticket book, it'll be me. I'm a writer, so I research for articles. I'm a teacher, and I need input for lessons. I'm an investor and need to know where the market is headed. I'm a horse farmer and need to know the latest in husbandry and training information. I'm a fanatic about current events and love to read new theories.
You'd think I'd be an easy sell on so many different fronts, but I find myself going to the internet first. I still buy books, but not nearly as many as I did in the past. And I look for bargains and for famous names whose information I trust. I've been eyeing
Empire of Debt for a couple of weeks and wouldn't have bought it at the $16.95 cover price (hardbound) if I hadn't heard Wiggins on C-Span yesterday and decided I needed to read the book
now. Still, I ordered it from Amazon, one-click, no shipping, as part of a two-fer.
That's a long-winded way of saying that the market is much tighter for books than for the other products and services you mentioned. It's about economics. If you could get the same quality legal advice for a cheaper price or free, wouldn't you do that? I buy more jewelry on eBay than I do at Tiffany's, though I can afford to shop anywhere. My "favorites" list is loaded with discount horse supply catalog sites.
The world is changing, and we POD and self-published authors have to keep pace with the economics of it all. It's strictly supply-side. If the goods are available cheaper, demand for you more expensive product will dwindle until the cheaper version runs out. The internet never runs out.
As with any other product, you're welcome to price your book as you please. If you want to sell it, however, it needs to be competitive. That's the bottom line. My non-fiction POD book at 100 pages and $11.95 plus shipping is overpriced. I do better buying it in bulk for $6.40 and reselling it for $10.00. That seems to be what people want to pay for 100 pages. And that's people who know who I am and trust my advice. At $10.00, they consider it a good buy. At $11.95 they need a reason to buy it. My autograph apparently isn't reason enough.
Rail on, but realize that you're fighting economics, and it's a tough battle to win.