It's important to keep a guard up against vitamins at all times. You never know when they might sneak past your battlements and make you all healthy and stuff. Image courtesy of BlogD. (used with permission)
One of the things that I did in Japan in regards to food was patronize the Foreign Buyer's Club. I didn't regularly buy anything, but tended to buy something that I hadn't had for quite some time. Unfortunately, they sell by the case so whatever it was, I'd be eating for a long, long time. One of the things I did not buy, but they carry, is Kool-Aid. My brother-in-law, who has lived in Japan longer than my husband and me and is still there, sent me the picture above with a comment which brought up something I had never thought of before. The fact that I've focused on Japanese snacks and beverages for years yet this never occurred to me is a good illustration of how we notice only those things in our frame of reference and the rest is out of our field of vision.
He remarked that Japanese people don't use powdered drink mixes except sports drinks. He said, "When I make up a Kool-Aid "On the Go" tropical punch drink in a water bottle, my students look like I am performing some freak chemistry experiment, and usually react with disbelief when I drink it. This, however, seems to be OK. I'd be interested in what, if any, reasoning lies behind that..."
It's an interesting question for which I do not have an answer. If any readers have an observation or speculation that they'd like to share, I'd be curious to hear it.