Update : My sponsor or whatever you call the person that introduced me to this site normally gets the benefit of me spending $$$ in the form of referral credits.
$10 gives him 200 credits, which is great as he can get balls with that.
However it appears that my spending of $20 which gave me 500 extra credits has not given him any referral credits.
My gain (500) is his loss (400).
No such thing as a free lunch I guess.