Yes, a very interesting topic. There have been several important questions raised already. Will food or drinks be allowed to be taken into the theater? Is the concept fairly simple, like pizza only, or will there be a full menu? Does the theater staff also work the restaurant? What are the hours of operation?
Still, it seems to me that Pieman has an advantage over many others who might consider adding this function to their theaters. He already has the facilities needed to get started. Not just the space to put it. He has everything. What else would he have to buy to give this a try? Maybe more insurance? Hire more staff? Buy more inventory?
If lack of marketing or fear of commitment to buy were the real reasons the restaurant didn't make it, then it seems to me that these obstacles would not be so difficult to overcome. How do you market your other products-- movie tickets and concession items? One way is through trailers and another is with posters. Do you think that a trailer advertising your own cafe upstairs is reasonable? What about a poster case with a nice poster or menu with prices? Or even newspaper or website or phone line advertisements or coupons. Seems to me that would alleviate some of the hesitancy to walk up the stairs. If people know what to expect, then they won't be afraid.
On the other hand, it seems to me that there may have been other reasons that the previous cafe failed. Were the prices right? Was the food good? Was the atmosphere enticing? Did the concept fit the theater? For example, if you are a discount house, I doubt many people will be willing to buy steak and lobster upstairs.
I tend to think that the simpler the concept the better it will work. Many cinema cafe type places in America tend to focus on pizza, sandwiches, and hamburgers. Others try to offer more choices. I think the more offerings you have, the more chances you have to get it wrong. Let's face it, your customers will probably be patronizing your cafe for one primary reason-- convenience. I'm sure some have succeeded by offering more choices and trying to offer the best food in town, but it sure does put more pressure on the business.
If you think there are too many pizza parlors, hamburger joints, etc. in your area, consider the reasons their customers patronize them. Do they go there because they have the best pizza or burgers around, or because the price was right and it was on their way? In either case, you have a chance to compete based on convenience. If you try to compete by having the best food, somebody can probably do better than you. If you compete based on convenience, you certainly stand a good chance of convincing some people that eating at the theater is the most convenient choice.
So, keep the prices reasonable and the concept simple. Advertise to your movie attending customers. Of course, you have to cover the basics of cleanliness, consistency, quality of product, and providing the correct atmosphere. After that, you will have probably overcome any previous handicaps and can compete on a fairly level playing field with the other cafes in your area.
Will that mean a big boost in income? Maybe not, but if you keep your costs down, then conversely it will not be too costly if you fail. It goes back to how much extra money is it going to cost you to try it? Can you afford to fail?