That’s a good point; An urban ecologist once told me the most environmental-friendly city is made of 6-floor buildings (like Paris):

- Ground floor: Shops,

- 1st and sometimes 2nd floor: Offices, lawyers, doctors, companies,

- 3-6th: Housing.

It was environmentally friendly because the density allows people to drop the car and go shopping and work with 15 minutes of their home.