Two things
1) Raking 60% of the prize pool seems quite excessive. Players pay a total of 25,000 credits in entry fees (it has reached the cap of 250 players every week for as long as I can remember), and WGT only pays out 10,000 credits.
2) Why limit it to 250 players in the first place, might as well allow more people to enter if they so choose (you can rake an ever higher % that way!).