Costco is the latter but it's a grocery store so their mechanisms are limited. Here's a Costco union busting just a few days ago: https://dailyiowan.com/2025/03/30/workers-accuse-coralville-costco-of-union-busting/

Also you should accept that every company with a union wants it gone and is trying to find ways to kill it. Hire more staff to non-union positions, shrink union positions, delay contract negotiations, close unionized shops preferentially, buy off union leadership with perks/collaborationism. Many a petite bourgeoisie has shuttered their union shop citing financial problems only to reopen a few months later, suddenly union-free. And of course, slowly whittling away union sentiment and pushing a decert.