They control the important aspects of the business. They control the pricing, they control how the drivers work, they control the condition of the vehicle (can't have an old vehicle, must be newer), and they exert control over when drivers work by punishing those that turn down too many fares.
The pricing, yes, although Lyft explicitly supports tipping and Sidecar actually enables differentiated pricing. Vehicles can be 10 or mor years old which is the vast majority of vehicles on the road (i.e., hardly "control"). And, yes, lights and seat belts must work (that's hardly control). They exert literally zero control over when you work. If you're going to open up the app and start declining fares, that's equivalent to a contractor turning in shoddy work.
