First, while you think that they [the male teachers] can gain benefit by being surrounded by women, to me it more or less seems that they are quite pitiful…
Reading is like adventuring and hunting for treasure: one may read ten books but not encounter a good book; there is already gain if one could find half a book that is good, perhaps making one to be as happy as the day is long.
In fact a lot of raw materials used in Japanese products are imported, so the cost cannot be determined solely based on factors in Japan. The value of Japanese yen drops, but the cost is also increased. There may not be benefits if you wait any longer!