Based on my observations of the video of Glenn Beckapalooza, I have found five reasons why participants in Glenn Beck's not-at-all-related-to-MLK's-"I have a dream speech" day are like zombies.
5. They both move slowly.
4. They are pasty-white, pale and unhealthy-looking.
3. They group together in mobs and react badly to those not in their groups. (More noticeable in this video of a distinct but probably not unrelated group.)
3. They are prompted to action by others who use them for their own purposes.
And, finally, the number one reason:
1. They both need brains.