Remember the lunches and dinners at Hogwarts? Magically, Dumbledore made the food appear in huge utensils, and after the stipulated time, Dumbledore made the remaining food disappear. Ah, if only this could be done in reality!
But eating in NBH/Yuktahaar isn't the reason I learnt to leave a clean plate after every meal. I just did, can't remember since when though. In my childhood, I used to leave leftovers many times and also disposed off my own leftovers and didn't really mind doing it. Since my second year I have considerably reduced food wastage and not because of any startling/shocking facts I might have read, I just did. And believe me when I say this, leaving a clean plate is quite satisfying.
Leftovers almost always happen, but leftovers in one's plate is under our control. Personally, I keep in mind the amount of food I eat everytime and take care not to take more than that in my plate and if I miscalculate, I stuff myself with the extra food! :D This helps me leave a clean plate everytime and hence maintain this habit. Perhaps, that's why I've been able to finish Hyderabadi Chicken Biriyani or Dominoes medium Cheese Burst everytime !!
P.S. - When I stayed at home, I relished the after party leftovers, especially chicken dish(es) or some other tasty dish(es), and almost everytime wished some leftovers be left because they were so tasty !! :D
P.S. - We must inculcate the good habit of finishing everything on our plate. Money may be able to buy food, but it can’t grow food, nor can it substitute the hard work of thousands of farmers. Wasting food is not a sin, its a blunder!