We assume pre-nuptial agreements only protect the person bringing in more of the money and property. But a well-crafted agreement can benefit both parties, even the lower-earning spouse.
As beautiful as a wedding ceremony may be, a marriage is very much a contract; when you say "I do" you are not only agreeing to love each other until death do you part, you are agreeing to be bound by the Pennsylvania Divorce Code in the event the marriage ends.
Hoping and working for the best is essential, of course, but so is preparing against the worst. When you get into a car you fasten your seat-belt, because nobody gets to take precautions in the instant they actually need them.