Actually I believe its this way because the priority was written into the code share contracts so Delta can't change it. At the other airlines Delta owns the seats so they can do it any way they choose if its not in the contract. The jumpseat war comment is interesting. I guess some people will never get the purpose of the jumpseat and the rules regarding its use and how hard some worked to restore the jumpseat after 11 Sep when the FAA planned to kill it forever.