I suspect it is/was a cultural thing. The Japanese market places a value on quality recordings. In the days when recordings were more often pressed in the market they were sold in you would see differences from market to market. The reason they started showing up in North America is that a small percentage of the population also valued that quality and someone could sell enough to make some money from the transaciton.
These days everything comes from a giant factory somewhere, so the same disc is just put into a localized jewel case.
