[thaumasiotes]

> You don't get to break down Zipcar's hourly pricing into just the hours you need to drive each way.

This is how all other vehicle rental works. It's the only advantage of rental over ownership.

> In the interim inbetween then the Zipcar isn't at its spot and therefore unavailable for other use.

That's just logistical incompetence on the part of Zipcar. Why would the Zipcar be unusable when not at "its spot"? My car doesn't become unusable when it leaves my driveway. The Zipcar is usable as soon as I return it to Zipcar. Their choice to refuse my return is just their commitment to an unworkable business model.