Lots of smart posts from experienced fliers here. My take on this:

1. It's a PR disaster that United made worse than it already was by the huffy, tin-eared way they responded.

2. The passenger behaved like an idiot. I'm embarrassed for him. Unfortunately for United, people have sided with him because the airline industry is widely reviled, fairly or not (I fly a lot and personally I find it pretty easy to navigate the system, but doing so requires patience and the ability to be resigned to one's fate). On top of that, United has a bad reputation for rude employees. I won't fly UA unless I absolutely have to, for that very reason, even though I once had a zillion frequent flyer miles with them.

3. UA and other airlines might think about a policy change. With more flexibility in extreme situations like this, they ought to be able to up their compensation offer until someone takes it. I'm not sure that would pencil out for them, though -- people would quickly take advantage and extort large sums out of them.

This will be a business school case study some day just like the Tylenol poisoning case from years ago now is.