Since the topic arose, FWIW, here in the U.S. it's common to have one power socket in a room (e.g. living room, bedroom) controlled by wall switch, and multiple

Since the topic arose, FWIW, here in the U.S. it's common to have one power socket in a room (e.g. living room, bedroom) controlled by wall switch, and multiple other power outlets lacking such a switch. I'm not in the industry, but I think the idea is that, in the absence of built-in lighting, one should be able to add lamps to a room that can be turned on/off by a handy power switch next to the room's entrance.