BTW, my library is loaner friendly. Better a book gets read than sit on a shelf. But unlike a traditional library, my books can be taken on perpetual loan. In fact, it's yours once it passes hands. I won't keep track or bemoan its absence. Once I've read it (if I've read it), I'm done. I don't reread. Too many other books to discover.
A few I won't lend out. Right now, those pertain to the book I am writing. So they stay close. But I don't catalog, like some music collectors do, organizing by artist or album or alphabet. I cram them where I can. Unload when I can.
A neighbor wrote recently she moved four times in the last three months. The books and papers were the kicker. To make her last move, she went paperless. She feels free. I'd feel naked.
PS--I won't mail a book either. I loan only in person.