[gpm]

Like when you buy or sell a second hand book without getting permission from the copyright holder to distribute their copyrighted material, which would otherwise be necessary.

[Y_Y]

It doesn't scale as well if I only have a single copy and don't make more. I daresay it won't be commercially viable.

[gpm]

Second hand book stores and libraries the world over have made it work

[Y_Y]

They typically buy more than one book.