it's not the number of spectators that will bring in the cash
it's the business-seats ,the vip's, the accomodations for beverages and food all that sort of stuff
granted they will sell more with a high attendance but one business-seat equals dozens of regular fans financially
the new stadium will also generate more income from sponsor because of the space inside and the attention it will bring
we never had the highest attendance in serie A yet we are one of the high players in Italy and that will improve with the new stadium