I think this may be somewhat true. I've bought over 150 books now on Amazon, and have only returned 1. That 1 was a Packt Publishing book which had a fantastical description, but after I spent an hour leafing through it, it turned out they had literally copy and pasted 1/4 of the material from drupal.org. Thus, I returned it "not as described". However, this was prior to Kindle.
As to your last point, I would have agreed, until Kindle came out, in which case with most books I can now get a free preview, which is usually enough to evaluate if a book is worth purchasing.
As to your last point, I would have agreed, until Kindle came out, in which case with most books I can now get a free preview, which is usually enough to evaluate if a book is worth purchasing.