Regnes said:
That's part of the premises of 28 Days Later, the zombies starved to death because they weren't actually eating anything to start with.
Also holing yourself up usually is a good idea, but usually the people in the movies are mentally retarded. Seriously, unless we're dealing with fast style zombies, a small group of able bodied survivors could easily decimate an entire city of zombies within a year or two. Establish a sanctuary and go balls to the wall killing zombies all day everyday.
First of all, why did you revive this thread? Zombie irony? I mean, I have little problem with it, but just why?
Secondly, there'd be far too many to simply go out "balls to the wall" killing zombies. Furthermore, what's to stop the zack following you back to base, and trapping you inside?
You fire a gun at one zombie, all the zombies in the area will go to the source of the sound, or worse, a zombie sees you and you don't see it, it moans, alerting zombies as it follows you, basically meaning if one zack sees and follows you, then a thousand will.
You'd have better luck waiting for them to completely rot (whilst going on very careful, stealthy supply runs) a process which (if memory serves) takes a few years according to max brooks.