I'm no expert on Japan, but the Imperial Conditioning I received in grad school is telling me there's a bit of essentializing going on here (it's not like awareness of Japanese literature in the West began with Murakami). However, a lot of interesting stuff here, like Hayao Kawai (whom I'd never heard of) and the "aesthetic solution". "In western fairy tales, Kawai notes, stories often resolve with a conquest, or with a wedding. Examples are numerous: Sleeping Beauty, Cinderella, Snow White, etc. But in Japanese fairy tales, Kawai says, there is rarely this kind of union. Frequently, stories resolve with “an aesthetic solution.” And by aesthetic, Kawai specifically means images from nature. ...the story is resolved by “the aesthetic solution,” in which the hero is left to contemplate his own existence against the backdrop of a beautiful image. Or maybe I am being too western here. Maybe his existence doesn’t matter. Maybe all we are left with is the beautiful image." http://lithub.com/our-fairy-tales-ourselves-storytelling-from-east-to-west/
This type of article suffers from a lack of sources and a wider scope - you cannot make such a generalization by picking a few stories which fit your viewpoint. Momotaro anyone? Why not start with the Otogizōshi which has lots of marriages, conquests and supernatural elements. Some stick out like hetromarriages between humans and non-humans. Issun-boshi should be mentioned if this was a critical analysis, but it is just reflecting on some ideas and going 'huh, that's peculiar' - it also draws the wrong conclusions. And seriously, the writer does not seem to understand what a fairy tale even is...