Disclaimer:
As letters don't convey enough information I'm not trying to discuss against you, I'm trying to figure out the rationale behind the problem
I appreciate the participation!
>> (1) I was wondering: why is there no standard to store annotations in an ePub book?
> 1. Because it's pointless for almost anyone interested.
Why is that?
>> (2) Couldn't you write highlights and annotations directly into the document?
> "adding to" or "changing" a copywritten publication (ePub) is a big no-no.
> Madness.
I don't see the "madness" or problem here. If you'd had a book, you would also write directly into it - even though the content is copyright protected.
> Really crazy to edit the existing files inside the epub
Why is that?