I doubt this is actually happening due to lack of easily compiled evidence. But, I was curious and looked into price discrimination law a little more. Apparently this isn't illegal.
Stated as a rule, price discrimination becomes unlawful under federal antitrust law only when it threatens to undermine competitive processes in an affected market. I.e. offering a lower price to one party who then goes on to outcompete the other party who you charge a higher price.
In general, there's no reason why it should be. If we were personally negotiating to do some job that I don't particularly want to do--and especially if I have other clients I could work for instead--I will probably charge you more (and you will probably be willing to pay more) if you really need something ASAP.
You need and receive an Uber ride just as fast in the low and high battery level cases. If the claim is true, they would be charging more for the exact same service delivered at the exact same time and pace -- not for earlier or more speedy service. They would be charging more simply because the increased psychological stress means they could get away with it.
I LOLed a little when I realized you really thought for a moment something like this could be illegal in the US.
(I have assumed you are in the US, as everyone else that does not specify the country in a topic that is clearly country specific)
Of course it does. It's just that in my experience living for extended periods in both US and Europe, consumer protection laws are a lot more advanced in Europe. It feels like business regulation in Europe is driven (mostly) by consumer benefit, while in the US is driven by corporate benefit (which a lot of US voters believe it equates to consumer benefit; you know jobs, etc)
Also the US tends to leave a lot more to the market and companies policies are more defined by the legal consequences more than the laws that prevent them to operate in certain manners in the first place.
Stated as a rule, price discrimination becomes unlawful under federal antitrust law only when it threatens to undermine competitive processes in an affected market. I.e. offering a lower price to one party who then goes on to outcompete the other party who you charge a higher price.