True, in cities these services works with more frequency. Had a friend that left a second car he had in the city, and he was monetizing it pretty good. After a while he bought another car and park it in the city too, business was going good and was able to repay second the car back! This is just one and the only case I know about carshare owners.

If this is a second car that stay parked in your garage without use, maybe worth to park it in the city!