Environmentally friendly meal

Had a lovely meal out last night courtesy of one of Tan's friend's husbands. Today we cooked in our house and had A Wu and A Ni around as per usual. I read recently that eating with friends is an environmentally-friendly lifestyle; you cook once for lots of people rather than 4/5 families cooking and each using energy. Of course that would probably be cancelled out if each family drove to the host family for food.