The word on r/uber is that in NYC if you don't cash tip your uber drivers, you start getting 1-star passenger ratings, and some drivers don't take rides from passengers rated under 4.6 stars.
Do you want inflated taxi fares of old, or do you want supply and demand? You can't have both.
Before or after paying the costs of driving?
There's tons of examples where supply-and-demand gets balanced with other considerations. It doesn't have to be all-or-nothing.