If the trip alone isn't enough to wear you out, being in a food court full of rude people, shrieking children, and people who hog the seating for as long as possible will.
Living in central Tokyo can be awesome. Your commute is shorter, you're near a lot of interesting shops and restaurants, and the public transport is convenient. That being said, Costco can't afford to place its giant warehouses in close proximity to the center, so if you want to go there, it takes about 5-6 hours round trip to shop there. It also costs between $10-$18 per person in train costs and requires the shipping of boxes of your purchases and a heavy backpack that you have to schlep back home if you don't have a car (and I don't). Once every 3-4 months, my husband and I wear ourselves out for a nearly an entire day to benefit from greatly reduced prices on many essentials. The fresh and frozen food in particular at Costco is much better than most local offerings, and monumentally cheaper. Given how expensive life in the metropolis can be, it's hard to simply say it's not worth the effort and not go. Though the benefits (in prices, quality, and selection) make the trip worth it, I dearly miss the days when we had a car and could comfortably drive to a Costco when we were back in the U.S.
I won't miss these quarter yearly sojourns and how exhausting they are.