Previous to this trip, I also shopped at Muji in downtown Tokyo, and at a Tumi at the Yokohama Outlet. Since I did not have scissors that I carry for travel, I asked the Muji staff to remove the tags on the pants the I bought so I could neatly fold it with my used clothing for travel back home. They said that they will not process my refund request if the item were considered 'used' prior to leaving Japan. In contrast, I asked the Tumi staff if I could use the backpack just on the day of my flight, and not the previous days while still in Japan. The salesman and the manager both scratched their heads and said that it should be "ok" but that it depends on the inspecting officer. I did not risk it so I just packed away the Tumi with all the tags still attached in my suitcase.

I am really curious now how things will change in the coming months.