It's obvious to me that Costco is trying to play both sides of the gun issue. They have no signs posted. They have absolutely nothing about guns in their membership information and agreement. But, they will tell you that guns aren't allowed if (1) you ask, or (2) they see a gun. So in my opinion they are tacitly allowing concealed carry because they don't want to stir up any controversy about it. I don't like their approach but I'm rolling with it. I carry concealed in Costco whenever I go there, which is at least three times a month. I guess their position is, what they don't see won't hurt them. Or, don't ask, don't tell. Or something like that.