[snir]

Lyft pairs one passenger (or equivalently, one party) to one driver. We've built a system which will actually take your route into consideration, and pair you with additional passengers that are en-route (relative to you). In other words, your ride is shared with other people heading in the same direction you are.

While are drivers are for-hire at this phase (in order to provide a reliable and available supply-side), there is much higher utilization in the car as multiple riding parties are paired to it.

EDIT:

I see the question was changed slightly. Higher utilization makes all the difference. Our current public transit system is just as you've stated: a vehicle being shared by "more strangers" (in your own words). We envision our system creating a completely adaptive and dynamic transit grid, which lends itself to predominant way in which people get around in the future.