I was going to type most of that in response to HT. They're not without their faults, but they're not as evil as everyone likes to make out. Some people really don't want to commit to working regularly or for a set amount of hours per week.
I wonder how many people will be protesting at the Amex to have this slavery put to a stop?
Seriously though, zero hour contracts work well for many many people. They become a problem in areas of low income/high unemployment where the employers hold all of the cards (As SOG mentioned above)...