How are Uber and Lyft not "world domination disruptive ideas"? The others I can see maybe, but completely revamping the automobile part of urban travel is a pretty big deal as far as I can tell.
Uber, Lyft are in the "self-driving car" category, not in the "more resource-efficient car" category. Put another way, they conserve a resource (attention) that is far more scarce than fuel, cash, etc.
Uber mostly seems like a better way to hail a cab in SF because hailing a cab there was previously next to impossible.
I am not sure how relevant it is in other cities but it will be interesting to see how they do.
In addition to the "can't find a cab" problem, Uber & Lyft sell experiences. This user experiences will be their biggest asset as they expand into other cities.