According to AusBT comment on the thread, the HNL stopover is mainly about timing for media and maximising publicity by arriving into SYD at 7am for morning TV shows.
They could still arrive at 7am with a non-stop flight from Seattle. Apart from that, what good will morning TV coverage give as from what I glean, those who watch morning TV would be Jetstar or Virgin customers - the Bogans of the world.