Indo the same if I notice the 0.01 upvoted.
Where do you believe the interest over your SP comes from and the accounts of the Steemcurators are funded with?

The witnesses do not receive this dust. They pay to run a server to generate blocks or to be able to let blocks transfer your data like posting, commenting, transferring Steem and SO
If blocks (those blocks creating the block chain) are created, they also create Steem. The top witnesses create most and receive (a part?) of this Steem as a payment.
If there is too much Steem the value drops, if there is exchanged toi much Steem (powerdowns) the value drops.

The only way to get rid of too much Steem (it is not different from printing dollars) is to take it out of the circulation. The so called burnsteem (by now burn SBD that isn't layed out).

The pool (rewards) is drying up, it is drained.
If the servers stop Steem is no longer generated but the blockchain also falls apart and no longer exists.