This is also part of our culture. The shooting of a Soviet intelligence officer in Finland, in 1942. In a second the person will be killed, but he smiles at the camera. But in everyday life we do not smile often.
That kind of statements makes any nation, that ever participated in a war... Revolution... Riot... Proud tradition of human beings smiling when they face a violent end of their life continues even today. Majid Kavousifar, 2007, Tehran, killed a judge. I am afraid, this is more of a humanity thing, than just russian, and has more to deal with mind snapping, than national pride.