... Uber offers some insurance, but only when there is a fare in the car. When there is no fare in the car, where is the insurance? There isn't any.
I don't think that's strictly true. The owner of the car has to have his normal private passenger auto insurance in order to license the car. In Vancouver, or BC in general, that's provided by ICBC. Uber's insurance coverage is supplementary and is intended to apply when the car is used as a livery vehicle. (In all honesty I have no idea how ICBC feels about this - does Uber's policy provide some sort of excess coverage and only pay amounts in excess of those paid by the normal private passenger policy, does it pay the whole thing in the event that there is a passenger in the car, does it cover the passenger as well as any other third parties (pedestrians, other autos, etc), and so forth).