So you meet a good, traditional girl who you want to marry and start a family with. You say to her:
"I love you. You are the woman I want to devote myself to until death and I trust you completely. BUT, here's this legal document I need you to sign so that just in case you decide to betray me you won't be able to take half my stuff."
See how well that goes over with her and her father.
So you meet a good, traditional girl who you want to marry and start a family with. She says to you:
I love you. You are the man I want to devote myself to until death and I trust you completely. BUT, here's this legal document you need to sign where I get at least half of your assets, will keep the house, get monthly child care payments dependent on your current salary (which you must keep since the court says I'm accustomed to this lifestyle), and maybe some alimony thrown in for good measure. Even if I decide to cheat and cause the dissolution of this marriage which I said until death, I still get what's coming to me, because, hehe, I'm not happy. I will lie and cheat as I please and if you dare so much to challenge me, you'll subjected to accusations in both the public and court arenas that you will lose, so don't even try.
See how well that goes over with you after it happens to you and for the rest of your life.
**note this didn't happen to me, but I"ve seen it plenty of times.