But against these benefits, there are costs to weigh.
Far from reducing congestion by encouraging people to give up their cars, as many had hoped, ride-hailing seems to increase it.
Bruce Schaller, a transport consultant, estimates that over half of all Uber and Lyft trips in big American cities
would otherwise have been made on foot or by bike, bus, subway or train.
He reckons that ride-hailing services add 2.8 vehicle miles of driving in those cities for every mile they subtract.
A new working paper by John Barrios of the University of Chicago and Yael Hochberg and Hanyi Yi of Rice University
芝加哥大学的John Barrios以及莱斯大学的Yael Hochberg和Hanyi Yi的一篇新工作论文
spells out one deadly consequence of this increase in traffic. Using data from the federal transport department,
they find that the introduction of ride-sharing to a city is associated with an increase in vehicle-miles travelled, petrol consumption and car registrations—
and a 3.5% jump in fatal car accidents. At a national level, this translates into 987 extra deaths a year.
What could be done to tip the balance back to benefits overall? "Congestion pricing is the most direct solution," says Jonathan Hall of the University of Toronto.
Several cities, including London, Stockholm and Singapore, have moved in this direction, charging drivers for entering busy areas at peak hours.
If ride-hailing firms tweaked their pricing to encourage carpooling, that would help, too.
One of the worst things a city can do, says Mr Barrios, is to cap the number of ride-hailing cars on their streets, as New York did in August.
That marked a step back towards the days when barriers to entering the taxi market were high and competition was low.
A dismal outcome, as most right-thinking economists would agree.