I once loaned a pattern book to someone at a guild meeting and I looked over and she was writing in it. I went ballistic. I have never written in any book and certainly do no expect anyone else to write in one that does not belong to them. Needless to say, she was offended, but I did not care, it was my book and I was doing her a favor, fortunately, most of it could be erased.
I was informed that she always writes in book. Perhaps, but not in MY BOOKS.