Why in the old days, brides had to sit in a sedan chair when they got married, worship heaven and earth, and drink a cup of wine when they got married.

No. You are watching TV. Just like now, rich people still find luxury cars, five-star hotels, wedding ceremonies, and drinks.

I will give you the simplest joke. Polygamy was a system in ancient China. Literally we can easily think that in ancient China, a man had two or more wives. But even from costume movies and TV dramas, we can see that only wealthy landowners can have wives and concubines. An ordinary man still has a wife.