Hi,
Thanks for the post and your question regarding the reward.
Currently adverts are not generating that much satoshi, so all that is received goes back into balance. The large satoshi balance that you see today is a thank you to all site visitors. Once the current satoshi balance reduces significantly I will then have to reduce the reward. Hopefully this news will not discurage you or any other visitors from visiting digitaldice.io in the future.
In light of what I have mentioned above I do plan on continuing to adding balance boosts from time to time as a continuous effort to say thanks!
Cheers!