Pros
Excellent and flexible scheduling, great coworkers, work is fast-paced and actually pretty fun. You will get a wide range of customer service experience, so once you've worked here, very little will surprise you at your future jobs. Management and the company are always willing to teach you new things and expand your work experience.
Cons
No raises. Period. That was ok prior to the recession when mostly students worked here, but now there are lots of folks who have their degrees and have worked here 2-5 years or more and pretty much have nothing to show for it. It's also a disreputable job - despite the fact that you will learn a lot and get tons of valuable experience, you'll have a hard time convincing other potential employers that your movie theater job was so valuable. Management is also very inconsistent.