It sucks but for United States based creators they have to protect their copyrights and trademarks. If they do not then others can actually forcefully take the IPs. Like a hostile takeover in a company.
If they do not protect against unauthorized use the owner can actually be stripped of ownership by the USPTO (United States Patent and Trademark Office). Best case scenario, their ownership is "weakened" creating precedents in court that unauthorized users can use to legally use the copyright/trademark.
This is why Nintendo is so protective of their IPs, to the point of taking ownership of Let's Play's and No Commentary videos on YouTube (Nintendo gets the ad revenue as it is recognized as a movie by law).
It is a sticky world messing with trademarks and copyrights owned by others for those living in the United States, or working with US based companies such as YouTube.
Some companies are more trusting of the community. Konami is one. They are rare though.
Sadly, all it takes is some asshole somewhere to ruin this for everyone and bring a fresh legal hell onto the retro community.
Wow, excellent explanation my friend, I'm really not as familiar as you are with all the copywrite and ownership policies in the USA. I really thank you for such a detailed explanation. But really, the Nintendo thing is awesome, especially the Let's plays part : O ...
Regards.
On one hand, copyright and trademark laws in the U.S. are archaic at best. Very constricting but for a reason, I am sure.