It’s a fairly known fact that the Japanese work ridiculously long hours each and every day which may explain why they always seem to be sleeping in public whether it be on the trains or in their cars parked by the side of the road which is not too kind on the environment with their engines running unnecessarily.
Anyway, if they’re not falling asleep they are trying to stay awake and it appears to me that so many tend to use eye-drops to help with this. Sure, some (particularly in this hayfever season) use them for other purposes but I’ve never seen so many people openly use them in public. I think the reason for such regular use is not just lack of sleep but also over-heated office air which irriates their eyes making them dry and red and so eye-drops are the solution.
Personally, I absolutely hated them when I was younger and more-or-less had to be pinned to the sofa while my parents added a drop to each eye so I guess I can now be thankful that I don’t work for a Japanese company and so can maximise my sleep if I desire.
Tokyo Fox (東京狐) 
I remember when my girlfriend used to work those insane hours and the want to do nothing but sleep on the weekend. Not only did I feel bad for her, but it also led to a lot of missed opportunities in the world of recreation. I see a lot of people struggling to stay awake, I wish they would reduce the unnecessary working hours, many of which are spent more trying to look busy or chatting than actually working. It comes down to a pressure to show your loyalty by putting i the hours and bonding with your collegues, at the expense of your personal life. Not for me, I’d rather have my own life (not that I necessarily have one!)