@Jenny349
I am a live in host, so I don't normally have to worry about guests leaving stuff on when they depart, unless I am away at the time and then, yes, it is something I worry about. My experience is that a lot of guests leave lights etc. on. Perhaps they do the same at home, I don't know, but I don't think people really care about other people's bills or wallets. That is why so many hotels have the key cards for lights/AC etc. which automatically turn off when the key card is removed from the slot.
So, I do expect a certain amount of this behaviour, but I wouldn't say I'm resigned to it. It's stated in my house rules and I remind guests about it when they check in. If they repeatedly leave on light unnecessarily, e.g. leave the lights on in their room when they are out all day and night, I will remind them again. Obviously, I do it politely.