Yeah it sucks, but the same rules apply to racing too. Although it would be great to see the event operate more like a showcase. Considering it's an invitational event, allowing everyone to have the chance to hang it out for the win makes sense to me. It's not as if its like a world cup race with 200 entries to sift through! It's also a judged event, so every year some one gets 'robbed', or someone receives a higher score than is perhaps deserved. etc etc etc.
Invite 20 riders. Let them dig, practice, re-dig, practice some more. Hold the main event on a Sunday and let them all go for glory.