I.E in a 4 bedroom, 4 bath home, there are likely 4 people living there, each person cleans their own bathroom,
Usually in high-bathroom-count houses, there are the “main” bathroom(s) and some bathrooms are mainly just used in the instance that the primary choice is occupied. Like when you really gotta take a leak but people are getting ready in the morning and bathrooms are in high demand.
Like forcing longer-running processes onto a different CPU when congestion occurs.
#1s are usually quicker and more time-sensitive. Nobody wants to piss in the backyard because someone else is pooping. And that has only happened while visiting a 2 bed/1 bath place. Fine for one, but five people overloads the resource, and the scheduler can't pre-empt the running process.
Really, the problem is that the bath or shower and the toilet are in the same room. Occupying the bath or shower should not exclude others from using the toilet. It's bad design that has propagated via real estate marketing.
Middle class Americans (petit bourgeois) might, but probably contract out for at least some of it; middle income Americans probably can't afford to contract out and probably do their own cleaning. But Americans often say the former when they mean the latter, so it's not usually clear what is being discussed.