Hays County 'moveable jail' looking to settle down

Here's a bit of Texas carceral history I was unaware of; reports the Hays County Free Press:

The Hays County Jail’s Moveable Jail Cell in San Marcos is one of nine sites that a statewide preservation group has named to its ninth annual list of Texas’ Most Endangered Historic Places.

The moveable jail cell was constructed for the Hays County Jail in Kyle and, today, it is a rarity of its kind. The cells were referred to as a “calaboose,” the Spanish word for jail, and were constructed using the cribbing method where the walls are arranged in sets of logs or timber in a log-style cabin formation to create a rising rectangle or square.

The jail cell remained in use until 1925 as Kyle’s city jail and, later, was moved to the Texana Village at Aquarena Springs. Due to lack of funding, the jail cell along with other buildings and artifacts were removed from the Village. At the eleventh hour, the jail cell was saved and moved to its current location at the San Marcos Academy.

The jail cell is a valuable piece of Hays County history but for generations it has been shuffled around the county. It needs a permanent home where it can be restored and appreciated, Preservation Texas argues. Local advocates are working to raise funds and to increase public support to preserve the moveable jail cell in order to tell a broader story of the county’s history.

Here's a picture of Hays County's two-man "moveable jail":

Looks like it could be mistaken for a deluxe outhouse! The story says "calaboose" is the "Spanish word for jail," but to clarify, "jail" in Spanish is typically "cárcel," while "calabozo" has more the dark, dank implications of the English "dungeon." Sitting out in the sun during a hot Texas summer, though, this structure would have felt more like some sadistic, claustrophobic sweat lodge.

Is there a place in the modern world for a moveable jail? What functions did mobility fulfill (work crews, perhaps?) that a stand-alone structure wouldn't? Or was it just the case that until 1925, Kyle didn't need more than that?

You can see the idea might be taken to an extreme, if perhaps in the realm of fiction. In my mind's eye I imagine prisons designed as mobile pods with prison transfers accomplished by cranes picking up whole sections filled with inmates and stacking them on trains like boxcars. Or then, perhaps I shouldn't give TDCJ any ideas!

A moveable jail ... who'da thunk?