However, while they will probably work well in a personal pinch during normal times, for a major wide area disruption (earthquake, major civil disorder, et al) they'll probably be no better that public transportation.
As I understand it, these are privately owned vehicles being used, and not company owned taxis. If everybody else is trying to get out of Dodge, then I would be very surprised if any there were any Lyft or Uber vehicles not already tasked with evacuating the owner's family and possesions.
You'd have better luck keeping copies of the local bus schedules handy. I believe that if it safe to do so, then they are required to run.