You may dislike buying used books like that, but the purpose of the previous owner wasn't to satisfy your future desire for a pristine copy. The purpose was his

You may dislike buying used books like that, but the purpose of the previous owner wasn't to satisfy your future desire for a pristine copy. The purpose was his own knowledge. If that's what works for him, so be it. It's his book. So it's a little self-centered to make this about you. It's not.