Pros
They do give you free call-ins to movies (call ahead an hour before, get tickets for you + immediate family members + 1 guest as long as it's not sold out). Everything else depends on location and management of individual theaters. They almost exclusively promote from within for Supervisor and Manager positions. Free popcorn and soda and discounted food/candy on breaks.
Cons
AMC views employees as a body in a position, they don't care about individual skills. Raises come MAYBE every year, year and a half and range from 5 to 25 cents. Under-scheduling depending on the competency of your management. Policy changes made with no explanation to crew members. Employees are treated differently based on whether or not management likes them (one person will get in trouble for something that no one else does). More managers are leaving than they can afford to replace, which IMO is really telling of satisfaction.