Here's the letter I wrote to Cinemark. I encourage you to share your feelings with them as well. Here's their contact page:
https://www.cinemark.com/contact-us.aspx
"To Whom it May Concern:
The horrendous shooting which occurred at the Aurora Co Century 16 has left me shocked and furious.
Your "no weapons" policy is disgusting. I know of multiple individuals who legally carry firearms for self-defense in Aurora, but who long since decided not to frequent your theaters due to this policy.
Last night, they chose other theaters in which to view "The Dark Knight Rises". It is possible that those legally armed citizens could have put a swift end to the tragedy that took place at Century 16. However, your inexcusable policy forced them to take their business elsewhere, thus leaving your customers defenseless.
I am appalled by Cinemark. If anything good can be learning from this awful event, I hope it is that "disarming good guys won't stop bad guys".
I hope that this gruesome incident will prompt a removal of the obviously ineffective "no weapons" policy.
I am truly sickened by Cinemark, and hope that the victims of this tragedy seek full legal action against you for creating such an unsafe environment.
Thank you for your time; my prayers go out for your company.
Sincerely, a legally armed citizen."