Looks like the tracker interface is listing the posts that are expecting a decent sized vote. Being ahead of this vote is a boost to your curation rewards.
I recently stopped giving prizes out for one of my curation leagues, because I see upvoting a post without regard to its quality as not how to Steemit.
You are absolutely right. It encourages potential low quality post boosting. Mind you, these posts are going to get massively boosted anyway not because of front running but because of bid bots allowing low quality posts to be massively boosted. IDEALLY, as minnows they should be able to profit off of the well curated boosted posts by adding to their pool and earning some curation rewards. This would be the case if bid bots didn't allow so much spam. This is more to explain it for people and let them do as they wish. I know my posts are quality and useful. I boost them, hence I want front running done for my posts to make them more noticed