In addition to the drawbacks outlined in other responses, human living situations are too unpredictable to make that kind of arrangement desirable. Inevitably,

In addition to the drawbacks outlined in other responses, human living situations are too unpredictable to make that kind of arrangement desirable. Inevitably, there will be a plumbing issue because someone left a bath running, or a medical emergency causes unforeseen traffic challenges, or a fire breaks out. The more delivery productivity you stack on top of this infrastructure, the bigger the impact from an unforeseen issue... and humans can introduce a lot of unforeseen issues.