This is ONE OF 2 responses to VC 25 Drury 13 ("Harumph!")...
Obviously, Drury, there will always be some jobs that will require people to physically do them, such as some of the examples you gave. But there are millions (no, let's be quantitative -- zillions, kajillions, mucho bagillions) of jobs out there that can be performed via computers. I cite John's elegant voice card on the subject (see VC 23 John 7). He is much more eloquent than I am on the subject.
But don't think the manual jobs that you cite are safe from the information age intruding on their turf. Take waiters. Not to put the legions of aspiring artists out of work who wait on tables, but it would not surprise me if the number of waiters is severely reduced in the next fifty years through the use of computers.
Here's how it might work: you go to a restaurant. The menu is computerized. To order, you just punch in a few numbers that correspond to your wants and whims. Then a real person would bring the food to you and ask in that cloying, insincere way whether "everything is o.k." With a computerized menu, one waiter could "wait" on twice as many tables as he/she normally would.