It is not that you can get anything by doing so. It is just decoration. Hence, the gentleman considers thenm ornament, but the common people think spirits are involved. I say, people have desires from the time they are born. When there are no limits imposed on how they can try to get it, they inevitably struggle for it.
Struggles lead to disorder, disorder to exhaustion.
The ancient kings detested disorder and lo instituted ritual and moral principles to set shares, thus satisfying people's desires and supplying their wants. They saw to it that desires and the supply of goods were kept in balance. Sacrifices are concerned with the feelings of devotion and longing. If he is greatly moved by his feelings, but he restrains himself and does not express them, he will be incomplete in ritual. Therefore the ncient kings established ways to fulfill the principle of honoring t-hose deserving honor and expressing closeness to relatives.