There was a proper stramash on book twitter this week when Alex Christofi posted a picture of some of his books cut in half and was promptly dubbed a book murderer. He did this to make them more manageable to carry around and read, and whilst it's not something I'd do myself, they're his books and I feel like he should be able to do whatever he likes with them.
I seem to be in a minority on this, but then it's also my habit to dog ear my own books, write in them, possibly highlight them (I prefer to use pencil, but I'll use a pen if it's all I have) and so on. Some of my oldest paperbacks are held together with sticky tape and still half falling apart. If the book belongs to someone else I wouldn't do any of these things, but neither would I lend a book of my own to someone. I'll give them away if I'm done with them, but lending to often means not getting back and that really is annoying.
The thing about the book murderer story that most disturbs me is not what one man chooses to do with his cheap paperbacks, but how so many people feel a sense of personal injury over it. It's a fetishization of the book as an object that I don't think is particularly healthy, certainly not when it comes to mass produced paperbacks.
I don't feel like a custodian for my books, they're mine to do what I want with. I might want to pass some of them on, but there are plenty that I've read and re read to the point of disintegration. There are others that will be outdated beyond the point of usefulness. Regardless, it's my choice what I do with them.
I'm not especially taken with the idea that you somehow have a duty to pass on books to the less fortunate either. There's no reason to assume that someone to broke to buy their own books would have any particular interest in the same subjects that I do, much better to have proper access to libraries that might reasonably have a properly diverse range of books.
The really important thing is that people get the chance to read the books they want in the way that suits them best, and if that means cutting them in half, fine. It does make me wonder if it would be worth looking at publishing books in multi volumes again. I'd much rather have something like that than one of those overpriced badly bound hardbacks that sit in Beautiful or Gift Book sections.