It's rude to down vote people's posts.
Tim is on Reddit and stumbles upon a post that is extremely disagreeable.
Tim wants to express his opinion and disagreement to the poster.
Tim doesn't rate the post but provides a comprehensive counter argument in response.
Tim down votes the post and responds with namecalling.
Tim is seen as a logical person who makes a good point.
Tim is seen as a troll and a hater by the other users.