I'd say this is a problem with the seller's communication, not the use of the book. If the seller didn't specify that the book was marked up, I agree with your sentiment. The act of writing in a book and selling it isn't the issue, but setting false expectations to whoever you're selling it to is.

> and it's a shallow way of taking notes to begin with

Are we really going to speak down to how someone uses a bunch of paper bound together? That's how they wanted to use it, which is cool, it's just not how you like it.

it's totally obnoxious to buy a copy of a book with notes in it and complain about those notes. 2¢

GP makes no mention of re-selling. They explicitly talk about revisiting. Your comment would have done better as a standalone as opposed to a response to them.

And not that it matters, but "cross out" doesn't imply "destroy beyond recognition." A simple strike-through is sufficient to keep the text legible (so you remember what it is you disagree with).

Probably the most treasured item I own is a novel a good friend of mine gave me as a gift. It was one of their favourite books, and they'd highlight lines and sections that resonated with them by putting brackets around them using a pen. Coming across those sections, and learning a bit more about them in the process, is like finding little nuggets of gold.

But I get where you're coming from as well. I guess it just really depends on the context of who/what/why when it comes to reading.

Aside from shallow, uncritical notes, consider that annotating in a margin is evidence that a reader is actively engaging with a text.

Very often when I write in margins it's to question or argue against what's written (e.g. "really? what about ...", or "no, contradicts ...") which, to me, seems in line with the dialectic process Socrates promoted. Multiple sides, truth-seeking.

Sure, having a spacious notebook on the side is even better. But it's the same goal, isn't it? Engage more deeply with a text and encourage questioning as you read it, while it's still fresh.