Quijotazo: Need a job ? Ask these guys ;)
Wait a second!
Despite of the T&Cs declaring that "credits have no monetary value" they are nevertheless translated into Dollars, fake Dollars to be exact. These guys may have won above 100,000 credits this month but NOT AT ALL the money indicated.
The Pro Shop will show you how some gift cards can be obtained with a much lower credit / money ratio, and the "Earnings" do not show the expenses in balls and entry fees etc. To be honest, they also don't show challenge winnings.
You should rather compare their career earnings to their time in the game - for the leader there it comes down to 10,000,000 cr in 6.5 years, theoretically translating to 200 $ per month - do the maths!
Sorry to say so but apparently you are one more guy who - greedily - fell for this breach of T&Cs, right on their front page.