By induction, sharing must not involve transaction of money between the two parties doing the sharing. A timeshare is sharing because the people who share the condo do not pay each other, they both pay someone else and agree on when each party will have access.
Also, Uber's claim to be 'ride sharing' is the idea that the rider is filling otherwise empty space in the drivers car. It's original purpose was to let drivers pick up strangers to fill otherwise empty seats while on their way to do other things, it just mutated into the 'driver as a profession' form that we have now, so I think it does fit your definition.
verb verb: share; 3rd person present: shares; past tense: shared; past participle: shared; gerund or present participle: sharing 1. have a portion of (something) with another or others.
You're the one making your own definitions...
By way of example; you and I may share a ride in an Uber drivers car. The Uber driver (as a profession) does not share our same purpose so is more accurately described as renting out their service and vehicle.
With example of carriers sharing a tower care must be taken to clarify the roles of the participants. If three carriers are using the tower then all three are sharing. Note the common purpose. If one of the carriers owns the tower then this carrier is also renting. There is nothing precluding both renting and sharing from occurring at the same time but to include sharing there must be a common purpose.
Since the dictionary definition of sharing speaks to a 'portion' with out regard to financial reward and rent is a 'payment for use' then the correct way to describe the financial transaction that occurs with an Uber driver is 'rent'.
As @kedean correctly points out; Uber may have started out as a service for sharing a common purpose but it is no longer that. The fact that Uber drivers are contractors, or in the State of California, employees is clear evidence that the driver and rider no longer share a common purpose.
As the word economy connotes finance and there is not a common purpose to portion out the more accurate phrase is 'Rental Economy'.
By the first definition of sharing on the dictionary, my argument is valid.
If you want to use another definition, than don't expect my argument to be valid.
If the car is used on Uber for (a very conservative estimate) of 20 hours per week, ~150 hours per month, that's about $1/hour in asset costs. Let's say maintenance and what not costs another 50% of that plus another 50% of whatever, we're still talking $2/hour in asset costs, which is far less than minimum wage.
"I would argue that the way it's traditionally understood, sharing is something that happens between equals, or people who have an intention of becoming equals."
Well, that's your definition. We can spend the rest of our lives arguing about definitions.
"From this perspective, it's obvious that CouchSurfing is sharing while AirBnB isn't: on AirBnB, the expectation is that there is a split between the seller and the buyer; on CouchSurfing, there is a shared identity of "travelers" and an expectation of reciprocity."
So, by my definitions, AirBnB is sharing, so is CouchSurfing.
"by your own definition of how you use the word sharing"
Again, you're implying a different definition of sharing than I'm using (or even that the dictionary uses).
"somebody might decide that their car is an underused asset which should be "shared""
The car yes, but you're not paying for usage of the car, you're paying for a transportation service.
"Well, so do AirBnB hosts when they clean the room after you stayed in it...)."
That's asset maintenance. Someone driving a car isn't asset maintenance, it's a service. And that's even charged separately, usually (as a "cleaning fee").
"tl;dr: Your conclusions don't actually follow from your implied definition of sharing, and your definition of sharing doesn't match the general feeling that the word evokes."
Not only you wrongly implied my definition of "sharing", which I actually took from a dictionary, but you also didn't understand the difference between usage of assets and labor services. Another way to look at it is: what's the main cost component? Is it return on assets or labor?
- Uber: labor
- TaskRabbit: labor
- AirBnB: return on asset