Simple reasons voting for comments is beneficial:

1. If we relocate more of the reward pool to comments people are likely to engage more.  
2. Engagement/Relationships = equal product loyalty and commitment 
3. It is a good start toward building communities.
4. Not everyone is a content creator, but they can add to the community via discussion
5. Save voting for posts for the best content, improving quality and possibly increasing traffic and decreasing frustration with spam
6. When you make a meaningful comment it is POR.  - I just made this term up.  Proof of Reading 

I am watching my feed and voting for comments on your post, as well as my own! Day 2

*In no way am I advocating for voting on spammy comments.

**Self-voting comments should be fine, I think about it in terms of adding value to the platform vs. comment, post, what have you.    Don't let others define how you should use your stake.  

Feel free to use and edit the graphic if you want to promote voting for comments.