Uber and Lyft retaliate--in ways that are at minimum unjust and in a functioning legal environment I'd bet a lot of money would be found illegal--for rejected rides.

Google doing it would be different, certainly. Companies are less important than people and poor people trying to survive get significantly more leash than multi-billion-dollar companies. If ride-on-demand companies operated with a transparent bid-ask system (see something like Taskrabbit for an example) instead of the opaque and intermediated market that they do, I don't think we'd be having this discussion. But they want to set prices and they want labor to shut up and take it, and that's not acceptable. To that end, yes, this is a fundamentally different thing than a multi-billion-dollar company controlling a market.