Here is Costco's email reply:
Thank you for your email to Costco Wholesale.
In reference to your inquiry on our policy disallowing the carrying of
firearms in our warehouse stores.
Costco does not believe that it is necessary for firearms to be brought
into its warehouse stores, except in the case of authorized law
enforcement officers. For the protection of all our members and
employees, we feel this is a reasonable and prudent precaution to ensure
a pleasant shopping experience and safe workplace. Our policy is meant
to protect our members and employees in all warehouses around the world.
This is not a new policy and we do not customize the policy for each
individual city/county/state/country where we do business.
Bringing a firearm into our warehouse does not enhance the shopping
experience. We are sorry the message you are hearing is that "we don't
want you." It is the firearms that we exclude in the warehouses, not the