The only lights I turn on are the ones in whatever room I'm in at the time. When I walk out of a room (unless it's only for a couple of minutes) I turn out the light.
I don't like to turn on the lights in the stairwell because, if the bulb(s) burn out, it will be one big headache to replace. One of them is level with the upstairs ceiling.....that's a long way up. That is where I have a water stain from roof leak during hurricane. No one wants to get up there to shellac and paint. The joys of owning a house.