Noisy toilets
Have you ever had some stomach issues in a public place and needed to use the restroom? But then when you find a stall and get inside, you are ashamed to do your business because of all the loud and awkward noises your body might make. Nobody wants to make other people listen to that.
In Japan, the restrooms are very advanced as we have already established. They have even gotten to the point where some of the stalls have a button that starts playing music or other sounds to drown out the ones you are making. Now you feel better and no one has to hear what you are going through.