The lavishness used to proof of that solid foundation.
Discussion
used to be that to join families both would have to show proof of worth. hence dowries separate properties etc.
I know. I had a lavish wedding in a castle with a designer gown, and etc. But we didn't pay for that! 😱 That would have bankrupted us.
Only thing the groom paid for were the rings and the honeymoon. Everything else was our parents.