Russians have a fascination with outdoor lighting, and whether or not it has anything to do with the early darkness that holds everyone in its grip, I have no idea. I've seen similar in Reykjavik, Iceland although toned downed quite a bit.
The Christmas lights were up and animated in Red Square by the time I left the city in early November, too. It brightens the spirit if nothing else. Landing in the dusk in Rochester, New York there were lighted homes dotted along the flight path.
Like other capital cities, weekends and holidays are for strolling outside with friends and family interupted periodically warming up with coffee or tea in a cafe. The Russians are "lookers" in store windows around Red Square, and the name brand European merchandise is way more than a typical Russian can afford on a skimpy salary.