Because the first stakeholder does not "pay" a post, they vote for rewards. The votes (both for and against rewards) are added up AT THE END, and then rewards, if any, are paid.
If someone wants to "pay" a post, we have a transfer function, and I think some UIs have a tip function too. That's paying. Voting is voting.
RE: After dedicating 5.5 years to Hive/Steem, I've been informed by KING ACIDYO that I added no value