Maybe I'm wrong, but japanese storytelling have a tradition of setting up such small things without even thinking.
I do not mean japan cannot produce bad writing, it's just such attention to details is a bit more prominent there.
Over here we have a familiar tale. But have some different detail, the kid come from the single mom after she saw a giant foot footprint and get pregnant. He eat rice, a lot of rice. And he using a bamboo as weapon
And no animal friend, But we did have another tale about a frog gather his new animal friends and go beat the shit out of god though