Don't use them unless you want that warm and fuzzy feeling of having legally obtained the Kickstart ROMs instead of just grabbing them from archive.org...
System ROMs were protected copyrighted works well before the release of Amiga in 1985. See the case of Apple vs. clone maker Franklin:
https://en.wikipedia.org/wiki/Apple_Computer,_Inc._v._Frankl....
What you describe is piracy. Your other comment about legality having a "bad reputation among Amiga enthusiasts" makes it seem like the Amiga community is one of criminals. That is sheer madness.
I think Gateway, and then Acer owns it, but who knows.
I used https://aminet.net/package/util/misc/GrabKickDisk to grab ROMs from my Amigas. But you can just as well grab them from random internet site, check the checksum and be happy and guilt free about it.
Acer never owned anything Amiga. The copyrights and trademarks can easily be looked up, while the patents expired before Acer even bought Gateway.
https://cocatalog.loc.gov/cgi-bin/doctitles.cgi?V3626D795 https://cocatalog.loc.gov/cgi-bin/doctitles.cgi?V9946D337 https://cocatalog.loc.gov/cgi-bin/doctitles.cgi?V9943D475
Please name one demo that you think should not be in Amiga Forever, and I will check that and report here.
I can't actually find this list of demos in the documentation though, is it online?
Me and my colleague Nicola were the ones who asked for these permissions. Iconic demos like Roots 2.0 and World of Commodore could not be included in the historical context for the reasons you mentioned. If someone does not want their work to appear in a commercial book project or in an electronic curation, I respect that. We could do better, like featuring more recent works. Perhaps one day it will be done, like the website (OTOH, some say that it has a Craigslist-like appeal to it). This always was a niche project driven by passion, and resources are tight.