You’ve paid for the cutout book jacket, and someone to illustrate your book. Why not also pay to make sure all the pages end in the same place? This ruffled edging is (I think) supposed to make the book look fancy, but really it just makes it hard to turn the page or to flip back through the book. I find my thumb traveling down to the bottom of the page where the pages are even, because that’s the only way I can turn the pages.
I have to admit that I’m fond of the “ruffled edge” look. It’s kind of antique-y. I could see why an author would choose it (although I assume that it’s actually the publisher who chose it). I never thought about it making the pages more difficult to turn, but I suppose I haven’t read very many books like this, so I just didn’t notice.