| The more people you have in jail, the more jobs you create. You'll need prison guards. You'll need prison construction. You need farmers to feed the prisoners. The prisoners should not be allowed to work, because that would be stealing a job from a law-abiding citizen.
This view is highly influenced by Keynesian economic theory - usually avoided by conservatives because it is considered more "liberal" than monetarist theory. However, even the Reagan administration engaged in this kind of economic theory by running up huge deficits with military spending.
It is an example of that old criticism - they know the price of everything, but the value of nothing. Simply creating jobs to do useless things does not help the economy. It is only busy work. FDR saved capitalism by using Keynesian economic theory.
In a market economy, price is supposed to be a reflection of value. The more valuable something is to the general population, the higher prices people are willing to pay for it.
Where this all breaks down is when there are a few people who can spend a million dollars on some ugly painting, while most people can't even spend that much on their housing. One ugly painting isn't all that valuable to the general population. However, because the rich can afford to spend a lot, the price of the painting is enormous.
Pro-capitalist economists don't like to admit this (of course), because it would mean capitalism isn't an efficient way of running an economy. Work involved in very useless things (like these paintings, like prisons, like the military) is being done, but only because somebody can afford to spend a lot on it. | 
