Modern nutritional science is also showing that the way food is digested and metabolized in the body is strongly influenced by a complex hormonal interchange -- and whether organs like the liver or the gut are predominantly responsible for macronutrient metabolism has a significant effect on, for lack of a better word, "effective calorie counts" in foods. The macronutrient composition of what we eat clearly affects our hormonal reaction, which clearly affects feelings of hunger and satiety. To ignore these feedback loops in favor of strict energy-deficit reductionism is a bit like saying that anyone not programming in binary is wasting his or her time.
Sometimes science literate ppl think these ketoers just don't understand the 2nd law of thermodynamics, but that's not the point. Its true that the 2nd law determines weight loss, but changing your hormonal response is how you really achieve a healthy lifestyle.
Further, many people would rather not have to track their calories everyday for the rest of their lives in order to maintain a healthy diet. They'd rather condition their body to prefer healthy foods, and to prefer healthy quantities of healthy foods. To do that you have to look at the source of the calories, not just the amount of calories.