Actually, it may make it convenient for criminals to know which houses do have pistols, if they're in the mood to steal some.
Just because a home has a weapon in it doesn't mean it's going to be able to deter theft.
This just makes it easier for criminals to "shop" for pistols. All they need to do is case the house for a few days and they'll be able to pattern the people who own the house allowing them to break in and search fro weapons while they know that-
A- it's an empty house.
B- there's a likely "reward" for diligently searching likely places where firearms may be kept.
C- it may be well worth the effort to bring a tool or two to specifically help defeat a gun safe.
D- if someone comes home they can be ready for them, and almost definitely catch them off guard and in the vast majority of cases unarmed. It may even be rewarding for them to hold someone at gunpoint and demand a firearm or ten. After all, they know the weapons are present.
After all, locked doors (including those on safes) are really just there to keep the honest, honest.
Are most homes robbed while people are home? Or while they're away?
The media has once again shown how irresponsible, unbalanced, and unconcerned with facts they really are. I'm shocked that anyone would be shocked.