This is 1000% a scheme by the prisons to make it as onerous and fraught as possible to appeal. They certainly aren’t going to help their ‘revenue-sources’ get out.

US prisons have tons of things like this.

• Prison commissaries are notoriously designed to gouge prisoners for small “luxuries”.
• Some prisons limit the list of allowed books to almost nothing (or force prisoners to use e-readers with per-minute subscription costs that are also exorbitant), or even use kiosks that they get very little time to access.
• Many states and prisons charge room and board while you’re confined.

All of it is done to both extract maximum profit while they’re inside, and to try to ensure people exit in debt, so they’re both hard-pressed to find work and desperate for money, because both things make people more likely to end up back in prison.