As the titel says.
The money bonus was never the thing that attracted the people, but the last reward at the end was.
Now I can see OFC that they cant just hand out gold, although it wouldnt be a bad idea, since ppl could see the difference between free mode and gold mode, and would give long timers something to check out for everyday.
Anyway the end reward could have a random bonus or at least have the money bonus scale up with your level.
Edit: This is the 5-day reward, not to confuse things here.