Now you have Uber joining the fray as "ride-sharing". No, these are professionally licensed drivers cruising around town in sleek, jet-black towncars. They are not "ride sharing" any more so than that restaurant is "food sharing" to me.
Some of these like Lyft or RelayRide are truly car sharing - peer to peer facilitating hitchhiking by unlicensed "cab drivers" for tips.
But still, the "economy" part is more in evidence than the "sharing" part. Obviously, people expect to be paid for doing services, even if it's an informal and off-the-books part of their income.