[prawn]

Ultimately, private prisons draw funds from those they hold captive, many of whom are imprisoned for minor issues.

[ballard]

The last part is agreed, but the inmates don't pay for their own incarceration (this aint Brazil yet).

The agencies that administer prisons get their funding from taxes, and the the level of funding maybe based on population.

But ultimately, society (taxes, etc.) pays for it.