Why did the father-in-law parade when his son got married?

One of the eight eccentrics of Hengshan Mountain in Nanyue, "My son gets married and my father wanders the streets", said that on his son's wedding day, relatives and friends put his father-in-law in a top hat, painted his face and wore a red robe; Hanging the sign of "grow old together", I went shopping with the groom and the wedding team, beating gongs and drums and attended the wedding. On the one hand, it is amusing, on the other hand, it also plays the role of warning education to prevent father-in-law from beating his daughter-in-law.