I don't think it's zero-sum, though. Before Uber/Lyft, I very rarely took a taxi, not because of cost, but because of the difficulty and uncertainty in being able to find and secure one (in SF). (I would either drive myself, and have to leave earlier due to the difficulty of finding parking, or take the bus, and have to leave even earlier due to how slow it is.) If Uber/Lyft were to increase prices to the same cost as a taxi, yes, I'd use them less, but I'd certainly use them more than I ever used taxis... because I'm getting a lot more for the money.