Even though Naruto is an orphan. How come he has absolutely no relatives? Cousins? Uncles? Aunts? Even family friends? Nobody seems to know Naruto.

And from the beginning of the series, I think most adults actually thought Naruto was the reincarnation of the nine-tail fox, not its container. Otherwise why would they hate him? They might fear him as a container, but they wouldn't hate him.

Probably its just some plot loose ends. Originally the Naruto pilot had Naruto as the human son of the Nine-Tailed fox. Kishimoto might have changed it to a baby container, but forgot to add in the necessary human connections he should have inherited from his dead parents.

That ... or Naruto is the Fourth Hokage regressed to a baby, after he tried to seal the Nine Tailed Fox into himself. But the personalities are so different between the Naruto and the Fourth, that seems far-fetched.