This is all actually $20 in Japanese Fun Bucks
Just as a cultural side note they don't actually have currency in Japan. Instead, you get these really neat redeemable gift certificates (Japanese Fun Bucks) that spend just like US money, but with no $$$ given back in change. The 1,000 vs 10,000. Bob Saget-san not included
Instead they just give you more gift certificates. In some ways it's just like AMWAY or going to your Aunt's house for Xmas.
Japanese Fun Bucks are redeemable at local fast food establishments, hotels, gift shops, and with several retailers. You can't redeem them for things like real samurai swords, priceless works of art, or teh sex. So they're basically useless.