Ever thought of trying a free popcorn night? We do this every Monday night. Not only has it increased our attendance (Monday is now one of our big nights now, right after Friday and Saturday) but our Monday per cap is often better than the rest of the week!!! We make up for the loss of popcorn income on drinks, etc. True, I know popcorn has the highest profit margin (by a long shot!) but it is also very cheap to give away. We give away 46 oz. popcorn cups and refills are free as long as they bring the cup back.
Also, what about trying self-serve soda stations? Many theatres are reporting good results with this. We will be trying it ourselves soon.
I've found that college students enjoy getting something for free, and will spend money when they do get something for free.
Rance