Why does vegetarian habit help us in getting more energy?

Why does vegetarian habit help us in getting more energy? In terms of energy who is at an advantageous position (vegetarian or a non- vegetarian)? Why?

Answer:
We know that, vegetarians obtain food directly from plants while non- vegetarians get the food from animals. Animals (herbivores) contain 10% of food energy as compared to plants (producers). For example; the same amount of producer which supplies say 1000 J of food energy to a vegetarian will provide only 100 J of food energy to a non-vegetarian. Hence, a vegetarian will be at an advantageous position.