Yeah, as someone who started with Costco rice and slowly moved up the quality chain, there is a clear difference in taste between even average Japanese rice and most Costco rice. It would be interesting to see a price/quality comparison between the U.S. and Japanese Costcos though.
This is one of these case where cross-country comparison might bring little relevant information.
Another example could be wine sold at US Cosco vs French Costco. It would be an indicator of something, but I'd personally be lost if I had to interpret it in regards to wine trends in France in general.