Last Friday I was looking for office supplies and equipment at the Costco in Nampa for my Security Business with my Wife, and as I had just got off duty, my Glock model 22 was on my hip. I have been in this store MANY times with my weapon and have never encountered so much as a dirty look from anyone, customer nor employee. I was approached by the Loss prevention manager and two floor managers and informed that it was against store policy to open carry firearms in the store and that they would like me to take my weapon outside (they were very polite for the most part). I was pretty annoyed by this as I check the exterior of every location I go to with my weapon and look for a sign that says I cannot carry, Costco had no such postings. I replied that I was offended and that they were not supporting my constitutional rights and that state law permitted me to open carry my weapon, but that I understood their position and would respectfully comply. As I was walking away, one of the managers told me that I should have known better and that the Membership Regulations stated as such. I said nothing as I new I was representing the open carry community at that point and did not want to escalate the issue. I secured my weapon in my vehicle and came back to the customer service desk and asked for a copy of the "regulations" only to learn that there were no such documents (I was met with much hostility when I explained that I was looking for rules regarding open carry). No "rules" or company policy could be provided. I thanked them for their time and shook hands with everyone, keeping a smile on my face the whole time. I will not be a patron of Costco any longer. This experience led me to Join. I realized that if we do not stand up for LAWFUL and constitutionally assured rights, we will loose them.