The goal is simply that all hours worked are for minimum wage. Under Seattle law, paying someone less than minimum wage is theft. Nobody is ignoring anyone's economic interests. They are simply attempting to stop wage theft.
Some work produces less than minimum wage value. Minimum wage was initially created to price minorities out of the market. Cutting off earning opportunities that people would do (and they're currently doing it) but that fall below that arbitrary earning floor only restricts total earning opportunities. That so many people seem to be willing to drive for ride share companies tells us it's currently better than any other alternatives and that they're willing to accept their current payments.