As far as that business model goes, let's just say that no one's complaining. Take a look at the table below, which shows various types broadcast and internet revenue.
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Every team can count on $30+ million every season without selling a single ticket or TV ad. That's good money. This doesn't even include revenue derived from Latin American TV contracts or other internet feedsharing agreements. The Extra Innings satellite/cable package pays out $2 million per year to each team as well.
So if you're the Giants, and you rake in upwards of $100 million in gate and concessions revenue, putting together a $95-100 million payroll doesn't sound all that bad even with the mortgage on the ballpark. According to Forbes, the Giants' 2005 revenues were $171 million. We don't have their books in front of us, but by using all of these bits of information and putting them together, we can come to one simple conclusion: The Giants can't cry poor because of the cost of the ballpark. They proved their financial health by heavily outbidding the Mets and Rangers for Barry Zito, and by showing their willingness to outbid the Astros for Carlos Lee.
Signing Zito is also a significant not-so-stealthy PR move. Zito was already a darling among local media, and the 7 or 8-year deal means that as long as he isn't traded (he has a no-trade clause), he'll still be there when the A's new ballpark opens. In the meantime, many A's fans will have watched Zito continue to pitch on the other side of the bay - either in person or on KTVU/FSNBA - which means more revenue for los Gigantes. If you're the A's, all you can do is hope the development process speeds up, because when Cisco Field opens up, the playing field in the Bay Area will be pretty close to even.