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We're using the author rewards of these posts to grow the stake of the topcomment account itself. We depend on delegations and as we have seen in the past, these are volatile. By growing the account we can create a steady base amount of HP for giving away votes.
Secondly we need these funds to pay out the delegators who get 80% of the curation rewards back in liquid Hive. That is why there is a scheduled power down on the account and I've set 50/50 Hive/HBD for these posts.

The curators get rewarded by a percentage of the curation rewards. These are based on the number of curations they do. This way, the more active a curator is, the more rewards they get.
The rewards are low, but at least it is something. And that is another reason to grow the HP of the topcomment account. The more staked Hive, the higher the upvotes for engaging Hivers and the more rewards for the curators.