Having worked in large corporate environments, I would point out that the chances that the Costco customer service rep, Camille W., composed this reply herself, is just about zilch.
I would be willing to bet that Costco, like most large companies, has a stock of 'canned' responses to most customer service questions. You will see the same phenomenon if you pose a question to an online help desk for a computer issue.
So although you may dislike Costco for dictating what people can do on Costco property, you should not criticize the support staff for merely relaying the corporate response. That response came from much higher up the food chain than the poor person who has to answer the emails.
Snohomish County, Washington USA