Two outlets show a bit of who they are by headline alone on a DEI story, here (neutrally reported), and here (biased).
Yes, the norm is go to the Costco outlet and buy and check out.
An item purchase where the regional Twin Cities Costco outlets did not stock the item led to a new member's having to use the website online ordering - me - and thus seeing the website for the first time. With Target under boycott for DEI capitulation to the fat guy and his fascist mean men Miller and Vought, a friend and the author's household both joined Costco, with its steadfast DEI policy remaining intact and not folded under pressure.
In the course of hitting and reading around the firm's website, there is a sitemap, where this page - note the full sidebar - was found about an Ethics Hotline for Suppliers.
Costco on that page's sidebar notes several praiseworthy policies.
Fascism need not successfully bully everyone, while trying to do so, and some nationwide businesses stand firm while others fold willingly to the fascist bullies.
Integrity that way matters.
Bottom line: Shop Costco while for separate but related reasons, boycotting Tesla over its South African fascist main man making a troublesome spectacle of himself in multiple ways and showing his limitations in more ways than decently self-controlled people do.