If they pay the driver more than they charge the rider which they have specifically done at points in the past, then every ride costs them, even if their other overhead is zero.
In the past they did this to achieve market dominance over taxis and lyft because they were drowning in billions of dollars of VC money, and the whole point of getting all that money is to become a market leader as soon as possible, even with loss-leading strategies.
In the past they did this to achieve market dominance over taxis and lyft because they were drowning in billions of dollars of VC money, and the whole point of getting all that money is to become a market leader as soon as possible, even with loss-leading strategies.