We have to admit we underestimated the importance of sitting for social interaction. Turns out it sitting is not only about relieving your legs. When people sit together they commit to a longer conversation. They may pick a place with a limited number of seats, thus communicating to others that they do not want to be disturbed. Finally, standing up is a convenient, but at the same time powerful message signifying the end of conversation.
Naturally we want to have all that subtlety in m33t.