There's only so much gas you could stock. Eventually you'd run out is the point. Not to mention most highways and interstates and even back roads would be clogged with vehicles. You'll be on foot more then you would be driving, your $1200 light would be rendered useless in the long run. No one, I mean no one risk going out at night during a zombie apocalypse, it's too risky, the living dead don't sleep...
I ain't skered. Science is on my side 7 Scientific Reasons a Zombie Outbreak Would Fail (Quickly) | Cracked.com
Pfft, keep reading that horseshat and you'll be laying there being zombie food wishing you'd spent that $1200 on an axe and some decent weapons.