And this is exactly the issue. Uber & Lyft offer a service that currently has certain regulations, but they don't want to be bound by the existing regulations because they are "different". Same issue with Homeaway, Airbnb, VRBO, etc.
The government has a interest in assuring that people offering a service meet some level of licensing, in theory proving they have some level of training and standard practices to ensure customers (citizens) are not subject to undue risk. But Uber & Lyft don't want to play by those rules. They feel they vet their drivers well enough and the government can go pound sand.
I think I'll create an app offering tooth extraction services. Use the app and someone will come to your house with a pair of pliers and yank your teeth out. Medical school? Sanitation? Pish-posh. That's old-school, big government think. It's a sharing economy now.