Dog-eared library books

I'm a huge supporter of my local library. Generally I read at least two books a week, stopping by there at least once a week if not more. I have always, since my elementary school days, been the kind of person who will use a bookmark to mark my place, and now I'm really annoyed that whoever had this book before me, countless people I'm sure, didn't have the common courtesy not to fold over the page corners.

Come on people. It's not your book. Return it in good order so that other people can enjoy it. I don't care if it is a $4.99 paperback copy of the book. You still don't dog-ear the corners. Grow up and act like adults, or stop borrowing books from the library.