[kube-system]

> Because they published it; they were free not to do so if they didn't want anybody to reproduce or distribute it

Copyright protects works at the moment they are created, not when they are reproduced or distributed. Most of the works under copyright protection have never been distributed.

[bandrami]

True, but not publishing also lets you keep them as trade secrets.

[kube-system]

Not really, copyright and trade secrets have different subject matter. There are many things could qualify as trade secrets but not creative works (e.g. a recipe), and many things that qualify as creative works but not trade secrets (e.g. a song).