The AMC Stubs membership is a paid for program that provides its members benefits in the form of upgrades on fountain drinks and popcorn. A 10 dollar reward is issued for every 100 dollars spent and can be applied towards the cost of food and drinks. The AMC Stubs program is not for everybody. As a matter of fact, you should probably avoid it unless fit one of the first two profiles listed below:
The "Movie Buff" - You watch a movie every week. At 12.50 a ticket, you will spent a total of 650 dollars in a year. This will net you 48 dollars in rewards (60 reward dollars - 12 dollar AMC Stubs membership fee). You probably are already a Stubs member.. If not, you know what you should be registering for right now.
The "I Eat Junk Food at the Movies Person" - You watch 8 movies or more a year. You love popcorn, and even more, you love washing down those kernels of joy with nice carbonated high fructose corn syrup beverage. You will receive 10 dollars back in rewards. This leaves you at a net loss of 2 dollars which can be easily made up by the savings achieved through drink and popcorn upgrades and refills.
The "Casual Movie Watcher" - You watch less than 8 movies a year and you don't purchase anything from the concession stand. You will lose money by purchasing an AMC Stubs membership.
If you are propositioned to buy the AMC Stubs membership by a crew member, buy it if you can profit from it, but turn down the offer if the numbers don't add up.

AMC Stubs Frequently Asked Questions

12 dollars a year
Allows you to get an upgrade in size for popcorn and soda purchases. Example: If you buy a medium popcorn, you get upgraded to a large.
When purchasing popcorn or soda, tell the cashier than you're using your Stubs card and you want a free upgrade from medium to large (for example)