See also: Bacon
BRINGING HOME THE BACON
The origin of the expression "bringing home the bacon" is uncertain. It might come from the English custom, which originated in the 12th century, of giving a young couple bacon if they were still happy after a year of marriage. Maybe it comes from the 'greased pig' competition at fairs, the winner bringing home the bacon (the pig). Or maybe bacon is meant to represent all food, since it is very ancient, having been a favorite of the early Romans and Greeks.
Another possibility sent in by a website visitor, November 2003:
European peasants c. 1500's could only sometimes obtain or afford pork, which made them feel quite special. When visitors came over, they would hang up their bacon to show off. It was a sign of wealth that a man 'could bring home the bacon.' They would cut off a little to share with guests and would all sit around and ‘chew the fat.’