To all those worried about VDB getting to expensive, it would be hard for that to happen in all but extreme cases, and the extreme cases can get handled by a separate policy. They key is that as long as a reasonable member of the general public agrees with the airline's definition of extreme, a PR crisis is averted.


For most normal circumstances, if you overbook 5% and have 1 flight crew that may need a last second deadhead, at most you're looking needing to appease 10% of the passengers. An airplane manifest, consisting of a bunch of strangers, 50%+ of whom aren't frequent flyers and whom, even despite of this incident, aren't going to know the rules anyway really aren't going to have the power to collude and drive the cost infinitely.


I think a more intelligent app is the key. As it stands, I think the VDB market gets inflated on flights TO hubs because they so preferentially want people who's final destination IS the hubs to be the volunteers. If the app of your trip shows your flight, plus the number of open seats on each remaining flights from the hub to your final destination (for say - 12 hours) it will allow people to navigate their situation much quicker. The gate agent can say "We need X volunteers to take the Y flight out of here 3 hours later", and with a quick glance the individual passenger can figure it out themselves if it will work and make a proposal to the gate agent.