as described in the game, and i have described this above already.
users have the option to purchase credits, which are basiclly extra turns, users do this to have a better chance of winning a round.
i will provide proof of earning etc... tomorrow if i can get time, i have recently split from a long term releationship and the paypal account is in her name so i have to ask her for access to the account.
this is not bull and you can ask scott who owns purepimps.com or worldhatred who owns trupimps.com that these games earn good money.