You are advised not to let anyone know you have firearms.
Why would I put a warning on my house?
4 Rifles, 6 shotguns and an extended pistol, hundreds of cartridges, hundreds of rounds as well as black powder as well as crossbows, longbows, black widows and some nasty military and hunting knives, all locked in my gun room, protected by an alarm, a dog and a SOTA locking system.
And still I don't want people knowing where it is!