Pros
Easy to get hired, anyone can walk in off the street and get a job, no pre-requisites other than passing a background check They are very flexible, you choose which event you want to work for, you can work as much or as little as you like
Cons
They will not tell you how much you are getting paid for most gigs, and in my case, they lied to me about how much I would be getting paid, my paycheck was very different than what I was told I would make. They do not treat people as humans, more like cattle. You are a nameless, faceless body to them and you will be treated as thus. They have some of the meanest people working there, you will get yelled at, you will get belittled, you will get treated like you are nothing. They are often very unorganized. They have a lot of people to staff each event, understandably, but they have some definite logistic problems.