Colorado law for concealed carry states that the theater could not impose a no carry zone. I have read several legal opinions on this and they all conclude that the law, as it is written, was not capable of being denied by local or jurisdictional statements to the contrary.
While the theater could have refused service to a CCW holder if they knew ahead of time, there was nothing they could have done post shoot out if one of their customers had been carrying and chose to intervene.
As discussed many a time on here I carry because I feel a responsibility for my own safety and don't rely upon anyone else to insure that for me. I also feel somewhat responsible for those that perhaps have not been as lucky as I in travels and eye opening moments.
Many folks are jaded as they have only lived in "safe" places, been around "safe" people and haven't seen the truly ugly side of the world, until it's too damn late. Many of us here have traveled and been in less than ideal circumstances, so we have a more grounded, realistic view of the world and what it holds.
I carry because I don't want to be a situation where something really awful happens and I have to live the rest of my life thinking that I could have done something to change it.