I'm just going to chime in here since I work at a 5 screen cinema.
As john9001 said, cinema's make all their money at the snack bar as we get almost nothing off the ticket. Our cinema got 2 copies of SW:EIII and after the first week was over, we ended up with our best opening weekend ever. Our ticket sells netted 13,000 bucks, the best ever for a cinema in this little town. However, the movie company gets 90% profit off each ticket, so that means out of that 13,000 bucks the cinema got 1,300. Bare in mind if that was our only income, we would be looking for new jobs now, however, even though we only made 1,300 dollars in ticket sells, our snack bar made well over 10,000 dollars in candy, popcorn, and drink sells, and that is 100% profit right there. So I hope you guys can understand why prices at cinema's are so high.
Also a little tidbit so you know how much cinema's have to spend to stay running. At our cinema it cost's us 15 dollars an hour to run 1....ONE projector and all its support equipment. (lamphouse, lights, exhaust, platters, automation, sound system, ect.) Times that number by 3 since Star Wars is 3 hours long. Now times that by 10, as for the first 2 weeks we had 10 shows of Star Wars running a day. If my math is right that comes out to 450 dollars a day to run 2 theatre's, and I'm not even adding in the fact that we had 3 other theatre's playing other movies besides Star Wars.
So please, next time you goto see a movie, spend a few dollars (if you can spare it) at the snack bar. Those people behind the counter will thank you as their paychecks and jobs are riding on it.
/rant off