That's true of any startup. But I guarantee you in one of those venture funding pitches someone asked them "So most cities have taxi regulations that make what you're trying to do illegal. How are you dealing with that?"
Their answer was basically "Fuck 'em, we'll flood the market with cheap product, make consumers love it and the regulators will cave." That would not have worked in Europe if they hadn't already done it in a bunch of cities across the US.