I just finished my mammoth salad for lunch and I am full! But I'm not worried that I over ate and I'm not feeling guilty about being so full of food because I know I didn't cap my calorie intake for the day on that salad.
Check this chart out! You will notice that the plant based foods are far superior to the animal based in nutrients and even supplies more protein. Only lacking in heart clogging cholesterol and fat.
Notice how easy it is to over consume on fats? The stomach receptors for the first two stomach samples won't send a red flag up to the brain that you are full yet with 400 calories of oil or meat, so you can see how you can easily double, triple or quadruple your calories before ever feeling full. With the veg sample you fill up faster, pack in more nutrients but consume far less calories.