Even if there were no disadvantage to upvoting a comment it would be worlds better. Every click on a comment is disadvantageous to me in that I could have pushed something toward the front page, right? That's my understanding. Obviously content creation counts most. Not even quality content. I don't feel like I even have to do the math. Even content that is meh-received has a better return on time investment, which in turn gives you more voting power (==free money.) If the comment voting system were prioritized, better quality content will rise to the top and I, personally, would appreciate much more the creators that were being rewarded.