Self Driving Vehicles

I've wondered why Google is spending so much money and effort on designing a self-driving car.  I've also thought about what would happen in society if most cars became self driving.  I've come to the conclusion that the world will be a LOT better off with cars that drove themselves.  I'm sure there other big societal changes that would occur, but here are some that I've thought about, and all of them sound very good to me!

1. Passengers will be free to do more productive things while riding in a car, since they won't have to worry about driving, navigation, or traffic.  That could be reading, writing, interacting on internet, or taking a nap.  
2. No more cab drivers!  The people doing those jobs now, will be free to do much more productive tasks for society, whether in science, art, music, politics, or engineering.  Currently cab drivers have a difficult time making a living.  Since they often have to wait for an hour in order to get a fare, they then have to charge more to compensate them for their non-productive time in order to barely make a living.  A computerized cab does involve a slightly higher fixed cost, but requires no direct labor cost.  (Maintenance, cleaning, fueling, repairs etc would require labor, most likely)
3. No more DUIs!  Drunk or impaired drivers cause a lot of horrible accidents.  The costs to society of those accidents is often very high!  Injuries or loss of life to breadwinners or employees is a huge tax on society.  That is why police spend so much time involved with DUI enforcement.  
4. Traffic law enforcement could become a thing of the past.  Computers should be able to navigate roads without violating reasonable rules of the road.  Some rules of the road may even be changed to adapt to the new capabilities of computers.  For instance, vehicles on open highway could "draft" in platoons which will save energy.  Computers communicating with each other would allow vehicles to drive with very little following distance between them so cars behind the lead car in a platoon will save on fuel.  4-way stops could also be a thing of the past, if vehicles approaching such an intersection could adjust their speed so they would cross an intersection at alternative times without slowing down too much or stopping.  
5. Because DUIs and traffic law enforcement would be reduced, it would seem that the tasks for a police force would also be reduced. Taxes required to support the reduced police force could be reduced, or the current police force could be moved to more difficult law enforcement tasks. 
6. Driver training & licensing requirements may be reduced or eliminated.  Certainly some specialty vehicles used for construction or hauling may need drivers, who will need licenses.  
7. Auto insurance will be reduced or eliminated.  If computers are controlling vehicles, they should eventually be much more reliable than human drivers.  They don't get tired, and they don't get distracted.  If there are fewer accidents, insurance costs should go down.  If the concept for self-driving cars becomes a "fleet ownership" system rather than individual ownership, those corporations may need some sort of liability insurance.  But even so, there should be no real need for individuals to buy insurance against accidents. 
8. Vehicle maintenance could be reduced even further.  Yes, computers and sensors involved with the self-driving capability will initially have some flaws in hardware and software.  But as we see with modern electronics, they will eventually become very reliable.  If cars become all-electric, there would be fewer "moving parts" that could fail, and the overall reliability should increase.  That savings in maintenance cost, will trickle down to all residents in cheaper transportation.  
9. Improvements to Homes and Cities:  If self-driving cars became "common carriers" and not privately owned, there could be many further benefits.  Homes could be redesigned without as much garage space.  Cities could be redesigned to be more pedestrian friendly.  Cars could be parked in underground garage in a "last-in, first-out" packed configuration, which takes up less space than a design where everyone can get to their car in "random access."