They also treat their employees well. (Not with free food or other so-called "tech" company nonsense). I have been impressed with the people from Costco I have met at conferences.
If you go in the back near the bathrooms, there's usually a wall of photos marked "25 years long service", and I noticed more recently one "40 years long service" (although a few of them had "retired now!" stickers).
That there's enough retention to justify that suggests they haven't burnt their employees too badly.
