Fat has been painted as the bogey man of the nutrition world.
But high fat in LCHF means that the majority of your calories will come from fat, not necessarily that fat will be high. It can be, but not necessarily.
In fact, Kim Dinis and I logged and compared a typical day in our old diet versus Keto and the amount of fat wasn't that much higher.
Fat has been THE ONE THING to avoid and for that reason the reminder/advice to increase fat is a solid one since it's very likely you are not consuming enough.
Plus when we start keto and while our bodies are not fat adapted (meaning, not efficient at accessing the fat stores) we will feel tired and lack of energy. The body will signal that this would be the time to have a snack, and most people would have been eating every two hours. Again, increasing fat makes you feel less hungry in between meals while signalling the body that this is the fuel it will get.
Eventually your hunger will come down. And you may actually consume less fat than what you used to on previous diets. That is fine. The body has plenty of fat to make use of. You may probably find later on, that you feel and perform better with fat above a certain amount.
Think of it this way. Keto is low carbohydrate (usually below 20g), moderate protein (enough to support and repair your muscles) and the rest is from fat, either the one on your plate or the one in your body.
Fat is to be eaten to satiety. Hence the phrase "Eat when hungry. Stop when full".