First of all, I'd like to put in my two cents about bringing food to restaurants, stadiums, and theme parks.
My kids do not drink soda. They either want chocolate milk or water. Two of them are lactose intolerant, so even the places that serve milk don't have *their* milk (Lactose-free). They are also slobs by nature, and can't always drink properly out of regular cups (unless they have lids and straws), so I do not feel guilty at all for bringing in my own drinks at restaurants. (Insulated sippy cups). If they offer little kid-sized plastic cups with lids, we get water. But not all places have those. We have never had anyone tell us to leave because we didn't buy our kids a drink. Even when we eat fast food, we buy the food separately with no drink (or water), or if we buy a happy meal, we get the "big kids" meal so that the kids can share, and then my husband and I drink the cokes.
All of the theme parks and stadiums that I've visited have specific rules about what you can't bring in, but there are no rules that state NO OUTSIDE FOOD OR DRINKS ALLOWED. From the size (dimensions) of the cooler, to the type of drink bottles (for example, no cans or glass), there are guidelines, but bringing your own food or drink to the game or park is not OUTLAWED.
So, all of the people ranting about those of us who choose not to buy concessions at parks and games because we're bringing our own from home can please get off their soapbox because I have read the rules on the websites of these venues, and it is well within my rights as a patron to bring my own food as long as I comply with their rules as to what types of food and drink containers I'm bringing in. (Oh, and just for the heck of it, I'd like to let you all know that I ALWAYS bring my containers back home in my cooler, or else I properly dispose of my trash or recycle so that the stadium or park is not cleaning up after me.)
Now that I've spoken my piece, I'll go back to the subject at hand. In my town there is a wonderful theater that serves food at the movie. Why go out for dinner before or after the movie when you can eat DURING the movie?! The movie ticket costs the same as the other chain theaters, but the food from the menu is delicious, costs the same as other bar/grill restaurants, and you can basically go spend money in one spot (one-stop shopping). Plus, the drink/popcorn refills are free and you don't even have to get up out of your seat and wait in line for them! (They give you a little pager thing, and if you need it, you buzz the server and he/she comes and gets what you need.)
Mind you, this is NOT the type of place to go if you have to sit in utter silence so you can hear every bit of dialogue in the movie. Servers going in and out might distract you in that case. But this theater is a wonderful place for a date or a special splurge for the family. So, even though I have an AMC Movie Watcher card and have been know to bring my own drinks and candy in (since my kids only drink chocolate milk, which you obviously can't buy at the concession stand and which I have to store in insulated sippy cups so it won't spoil; I also didn't realize until I read this post that they were enforcing it), if I am going to see a first-run movie (which is very rare), I'd rather support the theater that serves a full menu and to which I can go without having to worry about all that. I mean, you're not even required to order food there. I guess someone could go and not eat at all, but it is the whole concept of dinner and a movie that made this theater a hit. I'd never think to smuggle my own snacks in there because it would seem ridiculous. Maybe a lot more people would buy concessions at AMC (and other chains) if they actually served pizza and burgers and margaritas and chicken wings, etc.