Mainly to please parents-in-law. I can buy you some better cigarettes and wine. Chicken, duck and fish, buy some for my mother-in-law It is also more affordable. Buy alcohol, tobacco, chicken, duck and fish in pairs, two or four like this, man. If your girlfriend has brothers and sisters or something, give them a little meaning.
It must be that the more you buy, the happier their family will be. According to your own situation.