There are plenty of people who will bid less. Last time I was bumped I think I bid $200, in that case it was an early evening flight and I knew that if they asked I was only going to take it if they got me home the same night, so at most it was a 2 hour delay and the difference between getting home at 10 PM and midnight is pretty minimal. In fact in that situation I did get bumped and they put me on flights that were scheduled and in fact did get in a few minutes before my originally scheduled flights. If you're doing an auction you're going to get people to accept much less than $9,950 depending on how long they'll be delayed for.

Regardless, the other part of getting people to take VDB is reaccomodation and the airlines need to be more creative. In the case of Dr. Dao's incident UA should not have been offering $800 and accommodation on a flight the next day, instead they should have been offering $800 and a six hour van ride that got passengers home that night.