Regardless, the ability of a company to provide transitory part-time labor should not be considered as an end in itself. A part-time worker whose earnings are subject to change at the whim of Uber's fare adjustments is even less likely to make major financial commitments than a part-time worker in a low-wage service position. This has a negative effect on the growth and security of the economy as a whole.
If anything, we should encourage the transition of these contract positions into "just another jobs." Those gigs on Craigslist will be available in any case.
[1] http://www.citylab.com/commute/2016/06/uber-subprime-auto-le...