When I left for my LDS mission, I took along some Aquafresh toothpaste because that is what we were currently using at home. Once I arrived in France and ran out of toothpaste I was pleased as punch to find that they also sold Aquafresh in the stores and I purchased it as a small token that reminded me of my family, normal cheese, and all things American. Back in the States, did I move on to new brands? I did not. Not only were they more expensive, but I wanted to use the same stuff I had used in my now beloved and far away adopted country. To this day I use that toothpaste. That's at least 10 years with a consistent tooth cleansing agent! 10 years!
What I'm saying is that I am a creature of habit who can make just about anything become an expression of nostalgia. However, if Costco stopped carrying my toothpaste in bulk, that would probably be the end of it.