You can get through the whole game without killing a single zombie - but you won't resist smashing a few, so yeah, I see what you did there. Although I still think fleeing shouldn't be as easy.
Well, I think this whole game was created so a potential biologist could go crazy, go to a bank, get all his money, build a secret lab and invent the zombie virus himself. I got a F*CKING ONE HUNDRED bullets, so I could buy an armor, only to go to mere 45 because of these damned super zombies. Guess what - as soon as was too poor for the good stuff, I met the armor merchant. Fighting the urge to destroy my keyboard, I've grinded through another two hundred days or so - only to find out that the sexy mustache armor is the last one out there and NOTHING CHANGES. So this is me, opening a secret lab. Just you wait, motherf*cker.