Is there some kind of tacit agreement here with the burglars of the world? Do you WANT the burglar to come when you're not there? It seems to me if someone is going to break in, you'll want to be there to take measures like calling the cops immediately and defending the gun safe. There's no duty to cooperate with these people or to make it easier for them.
Well in my professional experience most of these are not super planned out burglaries. Rather they are crimes of opportunity. Its often tweekers looking for indicia that people aren't home, knocking on the door, and then if no one is home they head around back and make forced entry.
I'd rather say hello via the intercom (and again it might well be someone I know) than have them decide to make a forced entry and then have to potentially use lethal force.