Here's the rub. I'm not "bothering" anyone. I am speaking true information about how IP copyrights work. If you create something using someone else's IP, the IP owner owns that work - because they own the IP. No matter how much any ROM hacker will say otherwise. If Nintendo or Rare or Electronic Arts etc...wanted to seek damages against your content, they could and they would win or you would be forced to settle, relinquish any claim to ownership, and hand over all of the code you wrote to them. This is because you don't have claim of ownership of the content, legally they can claim ownership.
You're totally off the mark. But go on then, prove me wrong. Prove that you are right. Name me one unofficial piece of work that became, simply because it was based on an official work, the property of the copyright holder and not the property of the person who made it. If you're right, then companies who made the original IP would always be claiming that the (good) fan made products actually belonged to them, so it would be easy for you to prove that you were right. Just google for some instances of this, and post the results here.
Show me all the fan made hacks of the Metroid games or the Super Mario games that are now being sold by Nintendo, since (according to you) when one of these hacks is made, it instantly becomes the property of Nintendo. There are lots of hacks of Metroid, Super Mario World, Super Mario 64, etc, and some of them are supposed to be very good. Yet I've never seen Nintendo say "That hack belongs to us", and then sell the hack without the hacker's permission.
And Portal, Team Fortress, etc don't count, as they were sold by their creators to Valve and co. Name me one. And I'm not talking about a few changes to the game's loader, or a few isolated bug fixes, I mean where the hack makes a significant change to the game.
Look, Zoinkity unofficially translated Sin and Punishment to English, right? But that doesn't mean that whoever made S & P now owns the translation code that Zoinkity wrote, it's still Zoinkity's code and he owns the copyright to it. S & P's creators can't just use Zoinkity's code on a S & P rom, and sell it as the English version, since that would be infringing Zoinkity's copyright.
If, say, I wrote a Harry Potter story and it was really good (I wish!), then I wouldn't be allowed to sell it, as J. K. Rowling has the copyright for Harry Potter, and I'd be infringing on her copyright. But the story I wrote is still my copyright, even though it uses (without permission) J. K. Rowlings characters. By your logic, J. K. Rowling would also own the copyright of my story, and be able to sell it herself, but that's not correct.