There's no discernible moral to it. There's no obvious reason that they chose to illustrate animals. There's no point they seem to be making. It's just weird.
The multiculturalism is almost Caldecott-bait. It's like it was specifically written to appeal to givers of children's book awards. It's not a bad message, actually, probably not a message at all.
It's pretty stereotypical. Very American, with the Fourth of July, baseball, Halloween, Thanksgiving, and the obsession with Christmas in December. There's not really much to it, with no storyline or message.
Basically, the message is, "Don't trust other people to give you advice, because they just want something for themselves." But if everyone acted that way, society would crumble.
It's just fun. There's nothing really to it, and no real point. But it captures the feel, at least as far as an outsider can, of the mind of a young child who is walking but not yet speaking in complete sentences.
The kid being obsessed with something like that is very realistic, especially nighttime rituals, but the girl is demanding something that doesn't exist.
It's a good message, and the illustrations are really captivating, but the story is very didactic. The message is very clearly "be yourself", and it hits you over the head with that.