I sent the following email through their "comments" page:
I am a shadetree mechanic who maintains my family's three automobiles. Over the past several years I have bought many parts from AutoZone, amounting to thousands of dollars spent.
I have been apprised of an incident which took place at one of your stores in which a robbery was averted by an employee with a firearm. I understand that this employee has been fired due to this being against your corporate "no guns" policy.
I believe this corporate policy is very short sighted and in this case is penalizing a loyal employee who successfully thwarted a crime against your business.
I completely understand and accept your right to set corporate policy as you see fit, and I accept this particular policy, though fail to see how it is helpful in any way. AutoZone's policy of simply complying and giving criminals what they want is absolutely no guarantee of a peaceful outcome. A criminal is just as likely to injure or kill his/her victim whether said victim is compliant or not.
AutoZone must now accept my right to take my business elsewhere, which is what I have decided to do. I know I am not alone in this decision, as I belong to a very large online forum, and word has spread regarding your acts in this case, and your corporate policy. You will be losing quite a bit of business as a result. In addition, I will be spreading the word to all my friends and family members regarding your policy, which will result in more lost business.
In short, the legal possession of a firearm by responsible individuals is in no way a liability to your company. However, if an employee is injured or killed by a criminal because (s)he was not able to defend themselves as a result of obeying your "no guns" policy it will result in serious liability issues. In any event, as I have said, you have lost my business and that of many, many others. If you change your policy I may consider coming back. The ball is now in your court.