If the problem is not enough space or money to house prisoners then my solution addresses the problem as much as yours - more so, as it would actually help with the crowding issues. Besides, if you're going to run a low-budget dungeon you'd best make sure the folks you throw in there to rot are really the worst-of-the-worst society has to offer and not just a bunch of negro street-loiterers in hoodies and illegal immigrant look-alikes.
Unless I'm mistaken, the concern was releasing people from jail to prevent spending the money to house them. It's simply a problem of justice vs money, hence the title of the thread. It's not about the lack of space or lack of money. If anything, spending less per prisoner would allow you to house more prisoners under the same budget.
I don't consider not having flat screen televisions, weights, etc as a "dungeon". As children, we have access to less than that under punishment from our parents. I do not have any sympathy for the lack of entertainment for prisoners.
If there's a percentage of prisoners who are "negro street-loiters in hoodies" and "illegal immigrant look-alikes", then yet again, that's an entire different issue. That has no bearing on the quality of prison of life because the prisons weren't made for the innocent. If the innocent are being thrown in jail, then that's another social issue that needs to be addressed.