Why no veg/fruit?: Phytates (whole grains, nuts, seeds, beans) and oxalates (spinach, kale, turnip leaves, dark leafy greens…) leech the body of calcium, iron, and the biggest one zinc (building blocks). https://www.ncbi.nlm.nih.gov/pubmed/1174496 The other concern with oxalates is kidney stones. We have seen many in the fb groups come in with pets with kidney stones from kibble diets. http://www.upmc.com/patients-visitors/education/nutrition/pages/low-oxalate-diet.aspx
Fillers: one of the major points of feeding a PMR diet is to get your pets off of useless fillers. To have your pets being fed an optimum bioavailable diet where they utilize effectively and efficiently as much as they possibly can from what they are taking in. Feeding matter they are not properly equipped to break down and utilize taxes the system unnecessarily and creates expensive yard fertilizer. http://dujs.dartmouth.edu/2011/02/turning-waste-into-food-cellulose-digestion/#.Wn2x9edG0b4 https://www.sciencedirect.com/science/article/pii/S0003996915001259
Their teeth are not designed to pulverize plant matter in the necessary way it needs to start proper digestion. http://rawfed.com/myths/omnivores.html https://books.google.com/books?hl=en&lr=&id=udCnKce9hfoC&oi=fnd&pg=PR8&dq=Feldhamer,+G.A.+1999.+Mammalogy:+Adaptation,+Diversity,+and+Ecology.+McGraw-Hill.+pg+258.&ots=vN3qrVZNNd&sig=39_mzLrlQyx-N8hCu4okEy1TyOc#v=onepage&q=Feldhamer%2C%20G.A.%201999.%20Mammalogy%3A%20Adaptation%2C%20Diversity%2C%20and%20Ecology.%20McGraw-Hill.%20pg%20258.&f=false
Cooking/puree has no effect on enzymes or phytates. So doing either is not going to help lessen the effect. In addition, if you are pureeing and cooking to mimic the digesta in prey you are sadly mistaken. Feeding common table vegs that humans typically eat wouldn't have been in their diet anyways. And it's nearly impossible to recreate the digesta of a prey animal so pulverizing and pureeing is not going to cut mimicking it. You'd need a very impressive chemistry set for that.