Is driving an automobile considered work? Why?

I am on the road everyday Monday though Friday and do about 6000 to 10,000 miles a month. My back hurts every night, my legs swell and sometimes I can hardly walk after I get out from behind the wheel,

You are stressed out by heavy traffic, traffic jams where you spend 2 or 3 hours sitting meaning you are going to be home that much latter each night.

So yep driving is alot of work

Since so many jobs consist of driving I would say so. No one wants to spend that much time away from their family to haul things around so they have to be payed, which makes it a job. Believe it or not its not really easy work. It may not involve lifting or things like that but I can tell you it is harder work than sitting at a desk all day. My dad was a truck driver and many other people I know. It's not easy having to sit behind a wheel for hours or even days and weeks at a time. But someone has to do it.

If it's a taxi or a delivery vehicle, yes., because you are performing a service that you are paid to fulfill.

It depends on the context. Driving a taxi- work. Cruisin' with your homeys- not work. etc. . . .