I believe one of the rule is everything bought or « produced « in the rooms must stay in the rooms (that’s why 8th floor wanted to buy clothes in the lobby It’s the only way for her to wear them outside her room) and they can move from room to room only by the elevator (that’s why the low floor were dépendant from the good will from higher floors to have their meal). Add-on I don’t think they have bathrooms or toilets in the lobby