Ah the dreaded zombie apocalypse. It's a fun way to stockpile ammo, talk guns with buddies and so forth. A wife of a friend actually got into the gun world because zombies made it more 'fun'. Then there is the PC idea, that could be too.
But truthfully, if you are willing to entertain the idea of the walking dead scenarios, it leaves your mind open to the possibility and even a mild preparedness for whatever is to come. Be it end of days, nuclear war, all in all civil unrest and then there is that biblical mess ensuing. Either way, stuff is gonna fly, and the people who take survival seriously might find it easier to prepare against nightmares than to outwardly express the fact that it's probably going to be humans who will present the biggest threat to our lives... And shooting zombies isnt illegal...yet