Don't get me wrong, I'm not saying that people should repost on a regular basis. It could start to bore your followers and thus damage your rewards, even that of the new posts.
All I'm saying is, that we dont get rewarded by Steemit for hitting the post button, but by users upvoting to content of a post. And I dont think that many will upvote the same content several times.
I dont really see the big issue in this. There are a lot more pressing cases of system abuse - and even outright fraud - going on on Steemit, which do much more damage to the community and the reward pool.