Costco
JS in the U.S. writes: "I am a Costco member in the U.S. and I am able to use my card at the stores in Japan. All I had to do was stop by the membership desk on the way in the first time and make sure that their system could access my account. I have to imagine that the arrangement works in reverse for coming to the U.S. The yearly fee is about the same translated between dollars and yen. A spouse can be included on the same membership without an additional charge. He or she will receive their own card.
"With my wife being from Tokyo, we like to take her family to Costco whenever we visit Japan. The price on the sushi and sashimi is absolutely fabulous. The same size trays of sushi are twice as expensive in the U.S. and much cheaper than any other store that I have seen in Japan. Her family stocks up on household and kitchen supplies, since the large size Costco packages are usually not much more than the tiny size at the "conbeni."
Costco also has some normal-size products, like bottles of wine; other products, like DVD's and books are sold individually and cheaper than other stores in Japan. But usually the yearly visits are enough for her family, since that is about how long it will take them to get through the gallon of ketchup.