And what's amazing is that now there are all sorts of different masks for different needs:
(blog.qlep.com)
Masks that have a small metal piece to shape it around your nose so that if you wear glasses, they won't fog up.
(item.rakuten.co.jp)
I suppose it's natural that if you use something often and a lot, people would put effort into improving it and making money from it. I have no idea if this is effective. I don't know if wearing masks has prevented others from getting sick. The amount of people wearing them during flu season is so much, it seems a bit pointless then. Are we trying not to mix up illnesses? Who knows? At least it appears as thoughtful. It's the equivalent of sneezing into your elbow, which I bet doesn't happen in Japan.
I don't see this trend taking off in the States anytime soon.