Joseann
Now I am cross. 
If people are leaving fried eggs, old banana skins and goodness knows what else in library books, why did I fess up to a little chew of one page by my puppy and give the library £16.99 when I returned the book?
It's because you have a social conscience Joseann.
Some people just don't care,they also tear pages out of books and return them or you find holes in the ones at the hairdressers in those magazines that cost a bomb.
One of my DD's dropped her school reading book in the bath and had to confess to me. We dried it out and I went and explained, we were let off buying a new one because we had confessed.