My dad was that way, we were raised to be very cautious about leaving lights on if we were out of the room more than a few minutes. Even if we came out of our rooms to have dinner, that 30 minutes or so made him upset if we left our light on. He would have had a fit if we left the t.v. on all night.
I'm not sure what my husband would do if he came home in the wee hours and all the lights were on, he might know something was wrong since I'm the one who is always going behind him turning off lights that he didn't turn off when he left a room. The door being unlocked wouldn't faze him, we rarely lock our doors. I do, if I'm here by myself late at night, but if he and my son are home, it doesn't bother me. I've often wondered if I were to fall in the tub and hit my head how long it would be before he came to check on me. :waitasec: