I earned $14,000 with the Grilled Cheese guys in August and I know a lot of other affiliates who earn far more with them. As has been stated, it takes time to develop a depositing player base. Once you have that the money will come.
I think what leads to frustration for affiliates is that they monitor stats in terms of banner displays/click thru/registrations. While these are indicators of whats going on Rev Share affiliates are not compensated based on those variables. We are compensated based on profits generated by depositing players.
You can have 5000 downloads and not earn a cent or conversely you can have one download and earn $40,000 (I have had single whales who have produced that sort of revenue) the key is to send quality traffic to the casinos and then eventually you will snare a few good fish and start earning money (this can take months).