It's a different style of introducing a fantastical setting compared to the classic exposition dump, or the clumsy audience- substitute narrator who keeps asking for explanations, but it's far more engaging if you just let yourself enjoy the ride for a bit.

For example, I believe that early on the narrator speaks about his mother 'going to Heaven' - you're supposed to be curious about what exactly that means, since it's clearly not the same way we use the phrase. You're supposed to look forward to the eventual explanation, and to trust that there will be one.

Of course if that explanation never comes, and the detail is critical to the plot, that's a failure of the author. But no different from any other plot hole - that's what reviews are for.