They may (or may not) retain a copy, but they
obtained one that they can keep whether or not they choose to. And that is a new, extra copy that did not exist before, and no royalty was paid on. A library book or a used book, is not a "new, never before existing copy".
And if you want to see just how "gentlemanly" I am, here's some deliberately bad pulp writing for your edification. (Deliberately put in the Public Domain by the author.)
https://www.mobileread.com/forums/sho...lden+coprolite