That sound you just heard going over your head...let me explain what it was. First, while some books are translated, last I heard the author's guild doesn't own amazon or adobe. Second, authors will sometimes translate things, but even when they do it's certainly not to every language. That job is generally done by someone of that other language group that wants to share it with others who read that language. The salient point was that the job of the author is simply to create the body of text - not to distribute it, translate it, or such. Division of labor is not all that new of a thing - I didn't make the soap I used this morning, did you?
Second, whether there's a chance someone will buy a book after they no longer need it is irrelevant; Google is making money off the book without giving money to the author, and you're reading the book without the book having been paid for (whether by you or a library).
The steady state of disks is full. -- Ken Thompson