Ghost has a good point, however not everyone makes the cut for each tournament. And one full PGA field tournament would be quite extensive; nevermind 15.
I think that it is disappointing that Phil and Tiger aren't playing in the Championship but it's obvious that Phil is on his way out of the spotlight anyway and has made it clear that family obligations and such are taking priority over winning money in tournaments.
I think the FedEx Cup next year will give players incentive to play more events because they won't be playing for money, but points. And points then lead to money at the end of the season. They should lower all the purses in the season events so the Tour Championship will be where all the money is - much like the Charles Schwab Cup for the Champions Tour (congrats Jay Haas.)
But I agree something has to be done. I will be anxiously awaiting both players return next season.