Navy showers

Navy shower, (when they turn on the water for a few minutes to get wet, turn off the water to soak down, then turn on the water to rinse off)is required on Naval vessels because they carry a limited amount of freshwater on the ships. I was wondering: “why can’t they have a water distiller on-board near the heat generating engines, that would distill sea water from the ocean for the showers. The residue, brine, can perhaps be used in 3-D printers.

Lo and behold, I googled it and brine is already being used in 3-D printing.

And I wouldn’t be surprised if the Navy has already installed micro distillers on their ships.