For figuring out on their own that their pediatrician who recommended
X brand of formula has regular visits from a very informative and generous representative of the company that makes that formula, and never gets visited by lactation consultants in the same way?
In other words, «Lite
Brand X» may actually have MORE calories than «Regular
Brand Z.» Also, some pets simply eat more
of the diet food to make up for lost calories, so even if you feed a lite
formula, measured amount is still necessary.