Craig,
The statement was "it might be the biggest event in this region's history". It did not specify it had to be in Seattle. My point being that far more people in Washington, and in the world payed full attention to the last Superbowl, than will to the open at Chambers Bay. They will be talking about the Superbowl win long after the winner of the open is forgotten.
There's a big difference between what event interests the most people and what event has the most economic impact. Nobody plans a vacation and decides to spend lots of money based on who wins a Super Bowl. However, if CB shows well, looks good on TV, and the pros and media give it a good review, you can't dispute the economic impact it would have on the area...and that's obviously why the locals care. Assume you've got 10 foursomes a day traveling in from out-of-town to play CB, at Summer Rates. Here's my amateurish economic impact to the area:
Greens Fees: $239 x 4 x 10 groups = $9,560 to Pierce County
Hotel: $100 per night (conservative) x 2 rooms per group x 10 groups. Average stay, we'll say 2 nights = $4,000
Food: $50 per person, per day, for 2 days (the KP people spent more, so this is also conservative) = $4,000
Rental Car: $100 per group (low, I'm sure) = $1,000
Gas in Rental Car: $25 per group x 10 groups = $250
Souvenirs: $50 per person (a shirt or something in the pro shop) = $2,000
Conservative back-of-a-napkin estimate of $20,810 per day.
And I'm not smart enough to figure out the tax impact direct to the state/county.
You can't reasonably compare CB to Pinehurst, which is an already established tourist destination. People will still go to Pinehurst if they pave over the course and pay the US Open on asphalt. However, CB and the PNW have one chance to get this right and lure people to town.