I think you were selectively reading his rules. GB said:
"Custom items can be recast and sold/given away if the person paid for ownership of the item or has an agreement with the artist."
If the agreement is for total ownership, then that includes the right to do whatever one pleases with it. This seems quite straightforward to me. The exception is if the agreement expressly precluded such action (which apparently was part of previous agreements by Rainman to do 1-off sculpts). Sure, it is good form to ask about this ahead of time, but if you pay someone for a pure commission, then once the commission is done the artist no longer holds the right to dictate how something is used.
I did not want to get involved in this discussion, since well Im sorta new to this board...BUT...as an ARTIST/ANIMATOR/DESIGNER for a major TV Network, and a FREELANCE ARTIST on the side, all our work is owned by the network...they can chose to do what they want with it when they want with it. Its stated in our contracts....we even had a meeting recently where we where warned that if we did outside work on company computers, that, that TOO would be property of the network. I just finished a freelance gig where i got paid and handed over all ASSETS (illustrations, designs, animations) to buyer. He took it in his drive, and the assumption is, he has the right to do what he pleases with it...its his...no longer mine...I was hired by him...I finished the job, I got my money, now if he chooses to destroy the drive that's on him, or if he chooses to take my animation later down the road and get it reworked by another designer, thats his choice as well.
Again, Im just speaking on behalf of an ARTIST being commissioned to create something. The person who commissioned it then OWNS it after job is complete... we just walk away to the next job in hopes to see our work in public...and theres been times when our work changes so many hands it different by the time it reaches broadcast..BUT again...its in our contracts. So we are well aware of it.