Anyway, one of the jobs I did back then was to move a Paradox db to Access. (Yes, this was a LOOOOONNNNGGGGG time ago.) It was for a company that provided goods to jails around the state for the commissaries, as well as providing food for the inmates meals. I recall doing double takes at the prices that they were charging for some of the things they were "selling". A simple small bag of Cheetos would be marked up 5 or 6 hundred percent. Sanitary goods might be marked up a thousand percent. The list went on and on. It was crazy. And it was, most likely, VERY good money for that firm.
I don't know if they have gotten rid of those firms, but that is one place where A LOT of money was being made at the time. The more prisoners there were, the more money that company would make. Because the prisoners would buy these goods from the commissaries at ENORMOUS markups.
Not only that, but I always thought there was a HUGE potential externality built into that business. I mean, this is just speculation, but let's suppose companies like this supply prisons as well as jails. Well you could have a prisoner that is allowed to buy Cheetos and Snickers bars and sit around and get obese for his 30 year term. Only at year 20 he comes down with diabetes, or heart disease. (Not surprising.) And the tax payer is actually stuck with the bill for the medical care for the last 10 years, even though those companies made all the money off of selling the prisoner the Cheetos that contributed to the heart disease.
That job really was eye-opening for me.