Every Sunday Tokyo shuts down the main street in Ginza (a prefecture of Tokyo) to allow the masses to go shopping in this high-end shopping district. The streets are lined with designer shops from around the world. You name it, it’s here. Consider this the equivalent of New York’s 5th Avenue, or Toronto’s Yorkville, but on a much, much larger scale.
This particular Sunday was warm for December, which I suspect drew a lot of people out to take advantage of the nice weather. However, Tokyo is so populous that this could be the norm here and just as many would be out on a cloudy winter day too. But I don’t see too many shopping bags, so maybe it’s the weather… 
