The use of the phrase "their creations" led to to think that the people being discussed here were the artists, not the rightsholders. Only the artists are the creators.
My argument is that this is complex because the system of legal rights is complex. The people that you think have them are often not the artists. I'm not actually seeing how you have argued against this -- have I misunderstood what you're saying?
Side note: I used to co-run a small electronic record label, and almost all of the artists who we released music by were just ourselves (with a few exceptions made for close friends, who retained all rights to their music). Given our small size and low profile, it was shocking to see how quickly some of our releases were pirated. Sometimes albums would hit soulseek after we had only shipped out the first 30 or so CDs (and no MP3s). We weren't in it for the money... it was just a side-activity while we were still in school, and any money made was just funneled back into the label so we could release more music, so fortunately the piracy didn't affect us much as far as we cared. But it was still incredibly surprising.
I was not endorsing anything. My intent was to tell an interesting anecdote that illustrated the complexity of rights. Sorry for the confusion.
My personal attitude (not endorsing it, though!) is that the artists are the only people who really count. That's why I contacted them for permission. Beyond the artists, everything is just legalisms and how seriously to take their desires is a legal consideration, not an ethical one. My anecdote does indicate this in action pretty clearly, but it conflates that attitude with the main point I was making (that this stuff isn't simple).
Why would the artists be the only people who really count, when they made an agreement to let the someone else handle the selling? Doesn't that by default mean that what the artist _wanted_ was to let someone else handle the selling?