The salesman stood outside the prison bus, inviting people inside for a brief tour. The price tag for such a vehicle? About $580,000. This bus, along with hundreds of other products and services, are on display this week at the American Correctional Association's annual winter conference in New Orleans. It has become the largest gathering of corrections personnel in the United States. The trade show ... offers a peek into the sprawling private industry around incarceration. Unlike other conventions, however, this convention is closed to the public, and the customers on the trade show floor are mostly prison wardens, jail officials and directors from state corrections agencies. The exhibitors are there to make their pitch for a slice of the $80 billion incarceration industry in the US. The companies aren't the only ones looking to earn money. In many states, sheriffs and wardens ... look to private companies to help pay the bills. They do this, in many cases, by taking commissions on revenue from goods sold to inmates - everything from phone calls and commissary goods to ... e-cigarettes. The whole idea of a system that exists for the purpose of keeping people locked up for profit creates all the wrong incentives," said Marjorie R. Esma, the executive director of the local American Civil Liberties Union in New Orleans. Such incentives, of course, can lead to more people in jail for petty crime. Look no further than Louisiana, which has been dubbed the "prison capital of the world" because of its high incarceration rates.