Why does the aunt who cooks in the canteen always "shake the spoon"? How to evaluate this behavior?

When we were in college, there was always a saying when our classmates went to the canteen, "We college students are fearless, and we are afraid that the aunt in the canteen will shake the spoon." So when we were cooking, the aunt in the canteen gave us a big spoon and shook it back and forth. There was almost no food in the shaking spoon, and then it was given to us.

But if you pay attention when cooking, the aunts in the general canteen will have the standard of shaking it three times. The first is to eat less, the second is to be afraid that you will get fat, and the third is to let you drink more soup and eat more steamed bread, that is, not to let you eat.

It can be said that this kind of spoon-shaking behavior of aunt in the canteen is absolutely undesirable. I don't know where they got this habit. This is definitely a bad habit. Why are you shaking? We all have to spend money, so you can save us as much food as you spend. Don't you have a number? Do I have to shake when cooking at home?