Just think of all the revenue the state would have gotten from thousands of gay marriages: You have license fees, insurance, space rental, caterers, planners, officiants, conventions, tux shops, dress shops, florists, bakers, bartenders, hotel rooms, all of which are taxed along the way.
So if we’re judging the merit of a Proposition based on how it affect’s the state’s bottom line, Prop 8 is a miserable failure.