>>Frying up yesterday’s soba (noodles) is hardly unique to the Japanese.<<
True, but it’s all in the name.
If you called a rice, veggie and fish roll sushi, it’s Japanese.
If you made the same thing and called it Gimbap, it’s Korean.
Same thing with a Gyro compared to a Doner Kebab. When it’s Greek it’s a Gyro, when it’s Turkish it’s a Doner Kebob.
Unaccountably the Czechs call it a koláč and once more, just like the Japanese, they believe it's a sort of confection or pastry and not a real man's food full of raw meat and fresh garlic.