You've got water bottles, bandages, flashlights, MREs, and ammo. All of that is useless without the single most important item a person needs in any apocalypse. A black t-shirt.
You ever see a man wearing a Hawaiian shirt take the head off of a zombie? You ever see a woman in a cardigan sweater fry a robot's motherboard? You ever see a kid in a romper take out an army of apocalyptoads without breaking a sweat? Hell no. Of course you haven't. That's because without a black t-shirt, you would lack the confidence to overcome the crushing fear that comes from watching the world fall apart around you. Want to make that shirt even more bad ass? Put a Zombie Squad logo on it. Bam! Bad ass levels increase by a bahjillion percent. You're welcome.
Don't take our word for it. Go to the movies. See for yourself. It's a known fact.
That's why the creators of Dead Snow 2: Red vs. Dead took the time to make sure the heroes of their new movie showed the common sense we expect heroes to have. They wanted their heroes to be so damn believable that you'd think they were standing in your kitchen right now complaining about the lack of variety in your whiskey selection. How'd they do that?
Why invent heroes when the world has them right there at your fingertips? So they brought in Zombie Squad, and then outfitted them in this bad ass classic t-shirt. You want to feel like you're saving the world from a horde of undead Nazis? Get out your credit card and buy this shirt. You want to soil your pants at the first sight of the flesh-eating damned? Just keep on wearing that rugby shirt.