My two cents, FWIW...
1. These companies do themselves no favors with all the various ways they feed into an "us vs them" atmosphere. Especially with their attempts to create an “every reader of a book should pay us for that book, or they are thieves" mentality...
It doesn't escape the notice of all those who share books through an office/neighborhood/family/friends/whatever “library." (The fact that it isn't technically the same, since a copy could be made and kept, is academic, if not pedantic, since (wild guess) most of them read them only once, anyway.)
Could someone abuse it? Yeah, but people tend to live up or down to expectations; the honor system is better PR than the Captain Queeg approach.
2. Making downloading a crime is a bad idea; it would be a poor use of limited resources and provoke bad will due to the authorities investigating/prosecuting people they “catch" downloading books... when there are so many reasons/circumstances a jury would consider excusable.
We can discuss the ethics forever, but as a juror, if I'm asked to actually condemn a person as a criminal for something like downloading a copy of a book he paid for in paper or is not for sale in his region, etc., I'm more likely to vote to fine the plaintiffs and authorities who wasted my time and tax dollars.
A few trials like that would be a PR, if not precedent, nightmare for the prosecution and plaintiffs, IMO.
(Dang, I got carried away with my 2 cents.
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