I have been trying to think this through. I did not know about the price dropping to six dollars for Movie Watchers Members. That might make a difference. For those who were not Movie Watcher Members I am more dubious. If AMC is your closest theater and your prefered theater. It might be worthwhile. The point is you have to spend $120.00 just to break even. Only then can you start reaping a benefit. I don't buy concessions because they are ridiculously priced. AMC a few years back tried affordable popcorn. I loved that. But it fell away a year later. Since I often use AMC's 6 dollar morning movies, I would have to go to AMC twenty times during the year just to break even. And that just isn't going to happen. The 6 dollar morning movie is the best program AMC has ever had. It got me back in the theater to watch small movies that don't have fantastic Tomatometer ratings.
Here is how you make it kind of worthwhile provided AMC still has its $4 for $5 offer. 4 for 5 saves you a buck at the concession stands. Using that in combination with STUBS might get you a large popcorn every time for about the price of a small. With a large or drink you get unlimited refills. Armed with one of these cups or tubs that is worthwhile savings. And it would be unusual for an usher stop someone at the door bearing fresh large coke or popcorn. For loners if you had the time you could consider your large drink or popcorn a passport to a double feature. Concessions is where the theater makes its money anyway. Its dishonest but there ain't no way you can't consider yourself being ripped off on a seven dollar popcorn or a six dollar soda.
As for AMC keeping records of your movies, it was already doing that on the Movie Watchers Program.
The idea of this program is the same as Costco. In spite of the good savings, most people really don't see enough movies at one chain to get back their membership money. If you start buying concessions that is a huge win for them because you are buying their food which even at a discount is at ripoff rates.