Re: @AC "easy to copy"
Maybe it would be worth it for a college student who doesn't want to pay $200 for a textbook, but for a $9.99 paperwork, no way.
If the publisher were to sell their textbooks in paperback form they might sell more. Even without copying the $200 textbook is apt to be sold second-hand and third-hand if $200 is overpriced for its market.
Copying unprotected digital data on the other hand requires no investment of time or money. Well, unless you want to KEEP copies of every book you read and every movie you see!
Errm. What about people who simply want to keep copies of every book and movie they've PAID for?
There is a huge difference here, and it is silly to pretend that difference does not exist.
You've given examples of the supply side trying to manipulate the market. Don't be surprised if the demand side demands the right to respond in like manner. If vendors receive legal protection they should also be regulated to prevent them abusing that protection; at present this isn't the case.