[mikeash]

Neither way is perfect, though.

For the queue, let's say Alice and Bob both make $25k/year. Alice desperately wants to get home to, I don't know, say goodnight to her kid and wake up early to get to work in the morning, while Bob is just going out drinking and doesn't really care about it that much. Is it efficient to prioritize Alice and Bob equally, or would you simply call it unfair?

In a surge pricing regime, Alice might be willing to pay, say, $50 while Bob is only willing to pay $10, and Alice will get a higher priority because she cares much more and her stuff is much more important. Isn't that a win?

I see where you're coming from with income disparities, but I think that talking about how it translates into problems with surge pricing is basically discussing the symptom rather than the cause. The root problem there is that one person can make 10x as much as another person without being anywhere near 10x more valuable. This causes a ton of secondary problems, of which the availability of taxis and taxi-like entities is one of the least important.