[JohnFen]

Well, we're deep into worthless pedantry here, but I love worthless pedantry.

I would say that despite the casual use of "share" such as in your example, that isn't really "sharing". It's bartering. The use of the car is predicated on getting something in return, so it's an exchange of value.

[Closi]

Regardless of if it's bartering or sharing, it's definetly not a sale :)

[JohnFen]

Yes, you have shifted my thinking on this a bit. Thank you!