In nearly every other room of the house, you're meant to sit down. The kitchen is optimized for walking between appliances. When the available seating is exha

In nearly every other room of the house, you're meant to sit down. The kitchen is optimized for walking between appliances. When the available seating is exhausted in the living room, it feels a bit strange to remain standing if everyone else is sitting, so you excuse yourself to the kitchen for another drink, where you find a number of other people standing and conversing. This feels less strange, so you don't see much point in going back to the living room. Once everyone has made the inevitable trip to the kitchen to freshen up their beverage, and gets caught up in a conversation in the kitchen, the living room gradually becomes empty, and at that point, nobody wants to go sit alone in the living room and miss all the action happening in the kitchen.