I haven't seen this book - but from what I recall of my own response to picture books or pop-up books when I was *little*, it's the wee details in the images and absence of fixed linear narrative which opens up a kind of 3D, impressionistic engagement with the story that is very potent to the young imagination.
Someone mentioned poetry above, and I think picture based stories, when well crafted, can evoke similar multiple levels of response & association, via subtle tricks of ambiguity and suggestion, as poetry can.

I don't have that kind of response now (though looking at paintings which beg questions or contain seeming illogicalities, or even imply taboos, can sometimes get close) - but I can recall the sheer *magic* of looking at picture based 'stories' filled with little evocative details, quite strongly.
I think young children have a very different way of perceiving the world than older children or adults, rather like a condition of full immersion in sensory experience - before more objective analytical ways of thinking become prominent.
If I think back, it's the way I recall it anyway.