Marketing rule: If it can't be sold as is, someone will remove the name and put the word Zombie on it. It will then sell with great success.
We could not sell Dried Seaweed so we removed the label and put Dried Zombie Skin on it. It's never sold better thanks to Rule Z.
No matter the circumstance, if a person asks why you own/bought a gun but rejects the answer you give them, the backup answer will always be "Zombie Invasion". This may also be the original answer.
If they reject this answer you are allowed to slap them once, open handed, accross the left side of their face.
If they remain unconvinced then run, you are in the presence of a Zombie and the invasion has started.
Seek shelter and conserve your ammo.
Rule Z-2: Always remember to double-tap.
John: Hey, check out this sweet new 12-gauge I just got!
Jane: Why'd you get a gun?
John: D'know, target shooting...maybe some hunting.
Jane: That's dumb.
John: Ok, it's for the Zombie Invasion.
Jane: Zombies aren't real.
John: <Rule Z> Yes they are!
Jane: <moan> BRAINS!
John: Oh God.<grabs gun and runs>