okay, so i skimmed through this thread and most people have answered 'no'.
my goodness!
the books in my collection are mostly from second-hand bookstores in the first place...but even with a brand new mint condition book that i LOVED reading, i would definitely lend it to a friend!
plus the thing i love about second-hand books is that they've been so well loved and read and experienced and enjoyed. you find notes and scribbles and memories embedded into them.
besides, i hate reading a good book and then not being able to talk to anybody about it afterwards. you get a whole new perspective on things. and good books are meant to be shared! it'd be silly to keep all that knowledge to yourself and letting it die away, one brain cell at a time. it's much more stimulation sharing books, sharing ideas, sharing experiences.
that's my opinion anyway.
but i'd love to one day start sort of a chinese-whispers...but with a book. one person reads it, scribbles in it, the parts they hated/loved etc, and then passing it on...and seeing if it eventually comes back, full of memories
or maybe i'm just too idealistic that way.