Yeah I agree with this completely. I'm not sure what the current guidelines/etiquette is on reasons for down-voting, but I saw someone cite disagreement with rewards recently.
My only concern about "over-rewarded" posts is how it looks to potential investors and new members. On surface level a lot of content might seem over-valued, but on the other hand those same people constantly come to the HIVE office everyday, and produce their content, as well as adding value to the community, which isn't so tangible from a surface level view.