Helping grow a whole new userbase would still allow you to pay back delegators and do something to grow the userbase in order to make future promotion actually attractive.

If you're a huge fan of Photographs of one very specific thing, and you create a curation community around that particular thing, then the reward is in seeing lots of photographs of that one very specific thing.

The same way in which patrons pay artists for their work, or a commission.

Or, the way in which all those people buying merchandise for a particular brand, sporting team, or other thing, allow there to be a proliferation of that brand, sporting team, or other thing to do more things.