That’s interesting because for my use-cases, ridesharing and on-demand car rentals are substitutable goods. Ever since I moved to SF where ridesharing is noticeably more cost effective, I’ve shifted my more towards ride sharing. If prices on car rentals goes down with this Uber deal, I see myself shifting back in the other direction.
It’s not so much in a city: ridesharing is a superset of usecasses for me that eventually led me to cancel my zipcar, since they only served the road trip case that a proper car rental does just as well. Having to walk to the car and return it in the same place is a huge hassle, and then having to drive the thing and gas it up puts it much closer to competing with rentals to me.
One use case where I default to Zipcar is picking up furniture / big items. Also, I like hiking in Muir Woods but there is no cellphone signal there. You can book a trip to, but not a trip from. Another one is when I want some privacy.