On the flip (karma) side, as a non-driver, Uber has materially changed my life. I rank it up there with google maps, cell phones, and SMS/imessage/whatsapp in terms of its impact. I can click a button, and in most major cities, have transportation, often at a price less than taxies that would sometimes never show up, in less than 5 minutes. The transportation is safe, clean, and polite (something I would also not have ascribed to taxis in most cities.)

And that's before it gets into logistics.