It depends a lot on where one's from, and/or what one's used to. I can only speak for Europe and larger cities in Eastern Asia: A rail connect from airport to downtown is commonplace, often high-speed, and is taken by the vast majority of passengers that do not have a private or hotel pick-up, including business travelers.
A fare of $100 to 'get across town', unless I was in a real hurry to make up 20 minutes of time for a really important point-to-point connection, would horrifies me, but occasionally the bullet has to be bit.
[For smaller cities without rail infrastructure, taxi/cab fares tend correspond to a lot less.]
If you think this is normal, you are in an elite group and only use people in your group to compare to. Even if there are a million people in that group, it is still elite.
Arguing that they shouldn't complain about crappy service or being harassed by authorities, because billions of others can't even afford a taxi is a pretty bad argument.
Person A: "We should be demanding that our authorities look more closely at the quality of water in our town. Having it contain high amounts of flammable gasses is not ok."
Person B: "But there's billions of people in the world who don't even have clean drinking water"
It doesn't invalidate person A's argument - yes, there's lots of people without drinking water or without the $100 to spend on two taxis. Yes, we need to do something about it.
We don't, however, need to completely disregard everything else until that problem is fixed. We're capable, as a society, of dealing with multiple issues concurrently.
As an American, I thought American taxis were expensive until I visited Europe some....wow, or even japan. It's all about the perspective.
Chinese farmers are in an elite group compared to African or even Vietnamese farmers...so what is your point?
"Most people in the world can't afford taxi rides like this so don't complain about how the police treat it"?
(I've been to Denver once - I took a shuttle bus from the airport to my hotel on Colfax (took long way around and was not that cheap) and the public bus back to the terminal which left from the central bus station, was cheap and direct.)