This needs to be expanded upon. During my recent trip to Japan (mostly Tokyo, not sure if that's representative of the rest of the country), everything was packed in a plastic bag. Pretty much each individual item (when we were e.g. shopping for ready-made food), was already packed in plastic, then was put into individual plastic bags, and then all of those were again put into a plastic bag to carry. I probably used more plastic bags in a few days than I would have in a few months in the West (UK)!