I guess labeling a group you disagree or feel uncomfortable with as zombies can make you feel more at ease with yourself and what not. But, really, if you asked a random person, most would consider themselves different and a non-zombie. I figure it's just another of those things that goes under the positive bias we tend to have about ourselves. Thinking ourselves better and more unique and others.
People think and reason. And it just so happens that a lot of people want a family, a somewhat normal job without thinking about the deepest of philosophical ideas (I assume it's something like this that would be considered zombies). It doesn't mean they are zombies, it just means they have different priorities.
Some also realize that society /or whatever have issues, but the individual tend to feel quite powerless about it and kind of gives in. I mean, how much do you guys on intpforum actually *do* about all the things you think is wrong and what not?
If you study various people, you do see somewhat how they reason and you see why they are what they are. Not zombies, just different.
I just think a tendency to label a group of people can make people a bit high horsey and maybe even bitter because they fail to see how people really ticks. Understanding people is a big factor when studying systems.