I can't speak to the senior rate and times although most theaters only have one matinee rate, but Cobb is one of two shared theaters, the other being the 21+ dine-in Cinebistro.
Their are two theatres. One is Cobb bistro where you can eat a meal while watching movie and the other you can take food and drink but not room for the dinner. I highly recommend the Cobb.
Not sure about senior rates. Part downstairs is called Cobb and upstairs is the dine in theater, called Cinebistro
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