I haven't finished reading the entire thread, but this is a topic I am very passionate about.
Sorry for the typos in advanced (darned iPad auto-correct).
I too used to see at least 1 movie a week while I was in college (15 years ago) I would usually go to a matinee after school because it was cheaper, but I also went to evening showings as social events with friends.
The decline in movie theater sales can be attributed to many things.
1) As many have mentioned, the prices have become prohibitive. The trouble with this, is that most theaters do not control the prices of the tickets. It was mentioned early in the thread that a theater owner was in the "pop and popcorn" business. This is something that is outside the theaters control and if Hollywood wants to fix it, they will need to come up with a different model.
2) My next point is that not all theaters are created equal. The theater in my home town (Bozeman, MT) is about 10 years old and has not been updated since it was built. I don't remember the last movie I saw there, but I find it hard to imagine they are using 4k or better projectors. The last movie I saw in a theater was "The Hunger Games" in Escondido, CA at a theater that is about 4 years old. The picture and sound was better than what I have in my home town, but still not "compelling". I would say that my bar for attending a movie theater has risen since I was in college. I am very interested in this "Cinetopia" I heard about in this thread. That sounds like it may provide a compelling experience. Love the bar (hoping that means it's a full bar, as in I can order a gin and tonic or long island). I am very interested in this.
3) to answer the original question in the thread, yes, IMO ticket sales are declining in part due to home theaters. The trouble I see with this thread is that people are comparing the various levels of home theaters people have, and thinking that you need to spend a substantial amount of money and dedicate a room (with treatments and such) to achieve this experience. The views on this forum are also biased. Most users of this forum expect a much higher standard or experience. However, think about it this way. 10-15 years ago the average size of a home television was 27-35" CRT, no HD, VHS was the dominant player, and it was rare that someone had speakers other than what came with the TV, let alone surround sound. Now, when you compare the theater experience to that, we are talking about a significant difference in the experience. So, depending on your definition of home theater, I would say it is contributing substantially to declining ticket sales. I would argue that the proliferation of 50" ( and larger) displays, as well as the simplicity and access of a HTIB (granted this doesn't or vide the same performance of buying separate components for audio, that's a different discussion) are widely considered "home theater" (there is another thread on here about this, but again different topic) and thus home theater is hurting sales.
4) Other aspects of the experience also hurt sales. Poor PQ and AQ, bad seats, crowded theaters, rude people, low quality food, etc are also contributing.
5) As has also been mentioned, movies at the theater just do not have the same appeal to the younger generation. Somehow I don't think stealing is as big a part of this as has been mentioned. They just have different preferrrences in how they are entertained. Perhaps this is why the video game market has ballooned? The question I would ask is why has my generation stopped going to the theater?
6) I don't have hard data on this, but it sure seems like movies are available on Netflix and red box much sooner than they used to be from the rental stores 10-15 years ago. It seems like it used to be a year or more before a movie went from theaters to a medium that could be rented or purchased. Since I only have to wait about 3 months to rent the movie, it makes going to the theater less compelling.
7) Some have argued in this thread that the content available at the theater isn't as compelling as it used to be. I don't necessarily agree here. I think the quality of movies (story and acting) made now is on par with what was available 15 years ago.
It is really sad. The idea of a date night with my wife and going to see a movie still has appeal to me, but due to the reasons above, we prefer to order take-out, rent and watch at home.