This article in Salon asks why books cost so much, and implies that the costs have increased dramatically in recent years.
Except they haven't. As the author notes:

When the prices of hardcover books are adjusted for inflation, they turn out to have remained fairly flat between 1975 and 2000.
Nonetheless, for those who remember the 1970s, the escalation in prices does appear substantial. Figures obtained from R.R. Bowker, the company of record for information about the publishing industry, show that, from 1975 to 2000, the price of the average hardcover book of fiction went up 200 percent to $24.96. Average prices for hardcover poetry and drama books increased 211 percent to $33.57. Nonfiction hardcovers went up 123 percent to $40.29. The largest increase was in the juvenile category, which climbed 227 percent to arrive at the current average of $18.40.
Still, adjust these figures for inflation and you get a different story, says Robert Sahr, an associate professor of political science at Oregon State University who studies media coverage of complex matters such as budgeting and economic policies. He found that the cost of hardcover fiction in real dollars had actually gone down 2 percent, while poetry and drama and juvenile categories had risen only a few percentage points. Nonfiction hardcovers had decreased in real price by 27 percent.
"I'm not very surprised," Sahr says. "Trade books are one of the clearest examples of a completely discretionary purchase. They have to be price-sensitive."
So why imply that the nominal increase is meaningful, when in the same breath you've shown that it isn't?