The point of the rates is to drive labor supply vs demand. If things are underserved raise the rates. A more complex model could be used but that had costs in processing and interfaces. Plus time vs cost trade offs could make it easier to game and make them look extra bad. Stupid tricks like trying to get there first in a desolate area charging obscene rates. A shared area up/down ticker algorithm would be harder to cheat and outliers more excusable.

The easiest solution I can see is essentially setting alert thresholds "tell me when it reaches $30/hr and I will consider it on the weekend".

I never used either side so I don't know their implementation.