The heart of this piece is the author's realization that (relative to their cover price) glossy, expensive cookbooks don't actually cost that much to print: "Until one-day I got lucky. Just by chance I spoke to the print broker who actually worked on the exact bid for that famous book. And he told me precisely: that super amazing cookbook that I truly loved, which at the time retailed for $50 and had won every award…
This is because they have access to a traditional printer and are able to order the volume needed for that price. A print on demand book from amazon that is 200 pages, full color will cost ~$15/book. But, that price is fixed whether you buy 1 or 5000 copies. Add in amazon's cut and you're looking to make 30% for each sale on amazon.com. If they handle distribution to bookstores you're looking at a 10% cut.
This is the option available to most self publishers and the margins are not that much better than going with a traditional publisher. Especially, because the author needs to front all of the costs for editing, design, etc.