Pros
You get to meet and talk to all sorts of people
You get to try and work with a variety of products
Reasonable hours and pay
Work isn't overly difficult
Cons
Some customers and Costco employees can be extremely rude and occasionally abuse their privileges (yelling at you and demanding things; cutting in front of others to get samples; letting their children jump around or hang off demo stations, even if there are hot ovens or sharp knives being used there)
Upper management changes rules and policies too frequently
(water bottles allowed at station, then not allowed, then allowed under special circumstances, then not allowed again)
Expectations set by upper management can be overly difficult or impossible to meet
(regardless of situation, set up and clean up should take 15 minutes, and sample tray should always be full)
Vendors can have unrealistic expectations
(push products constantly, even to people who can't use them; sell thousands of dollars of merchandise in a day, even if customers are saying it's too expensive)