Disagreement of rewards is a very fair reason to downvote.
Stop freaking out about a downvote. It’s a shared pool and people can use their stake to redistribute some of that inflation when they disagree with what a post has been valued at.
To be perfectly honest, I usually want to downvote most 3speak posts on trending. It’s sort of absurd that one group is allocating so much of the inflation (and using Steemit Inc. stake) just to better themselves and their project.
Make your content, enjoy yourself, and don’t get so worked up over an downvote, they are part of the system.