Curiosity only.
Here in Brazil it’s very common to have several showers a day. I, for example, take two. The first is when I wake up, before I go to work, and the second is when I get home from work. I wake up at 6.30am and get home at 8pm.
edit: I said bath, but I meant shower.
geothermal power exists.
Hot water is also a waste byproduct of nuclear power generation. There are whole towns that use nuclear heated water to warm their houses and for hot water. It’s used quite a bit in Russia and china already
https://www.powermag.com/district-heating-supply-from-nuclear-power-plants/