Fair enough.

I always assume someone will inherit my books, either when I die, or because I gave them away as gifts or exchanged them for other books at a used books shop.

This is my stance by default, but let's say there's a book I love which I never intend to part with, even then I would feel bad about crossing words out. After all, if I love the book, what's this "violent" disagreement/scribbling about?