I would assume it takes far more energy on heating/cooling/ventilation systems for large buildings in general than it does for a series of small buildings that have classic ventilation systems called "windows that open to let in fresh air." Something that is pretty rare in office buildings.

EDIT: Furthermore, large buildings usually have automated systems that keep it roughly the same temperature throughout the whole building while individuals in their own homes might try to keep heating/cooling bills low by choosing to only heat/cool specific rooms that they're actually physically using. I know I certainly do this at home, no sense in doing temp control in a room no one is occupying (other than making sure it's above freezing for pipes, etc.).