I think anyone who doesn't want to sign one is living in this fantasy, fairy tale, naive, gullible state of mind.
Common! PEOPLE!!! You came to this world alone, what makes you think this is a "ride or die" world!?
Both party's attorney will go through the pre-nup and give legal advise so it's not like someone is trying to pull a fast one. If no deal, then just don't get married.