Otherwise USA rice is imported in Japan, as well as other countries' and is indeed way cheaper, but not desirable and people aren't literally starving either.
In fact the US produces plenty of Japanese rice (Japonica)
Indeed, I bought some and it was good. Italy also grows Japanese strains and it also of pretty good quality. Those are not cheap either, though. I'm assuming that's not the Costco rice parent was referring.
> This is why prices remain high.
It's complicated, and no single factor explains it all. Even singling out importing rice, Japan has better options than the US (the SEA region is a much more logical source for instance)
On the "it's complicated" part, believe it or not, Japan gov is/was actively restricting rice production as a long term strategy.
> Do you think someone who is poor would not buy cheaper rice that had 90% the quality if they could?
That's ignoring all the other options, in particular wheat (bread, pasta, noodles etc.), which can be cheaper than cheap rice. It doesn't match the cliche, but Japan has steadily included wheat as a staple over the years.