To people who don't know, part of the core of Costco's business model is curation, which leads to customer trust. I know that almost any product that I buy at costco is going to be high quality. I know that anything with a kirkland brand on it is going to be so high quality and so cheap that it feels like I found a cheat.
What's funny about costco is that their in store experience is so good that they have seemingly ignored any sort of online presence. Yeah they have a website, but it doesn't seem to actually have a comprehensive list of everything they sell. You have to go to the store and check out what they have (and get a hot dog or a piece of pizza while you're there)
If there was a delivery app that curated restaurants, I would absolutely love it, and I also think it would be really successful.