SUBREDDIT: r/AskReddit
TITLE: Why doesn't Reddit have a way to regulate troll accounts? Or does it and I just haven't heard about it?
POST: Besides the mods banning by subreddit, I mean.

Just wondering. It always kind of irks me to see someone only posting negative comments. In my opinion, Reddit is much better and shouldn't be a place like that.

Granted, it'd be difficult to put a report button, because that would easily be abused. 

Possibly something could work such as posting "x" number of posts that receive "-y" amounts of karma gets your account banned for "z" days. This way, trolls can't go on a daily spree and fill Reddit with useless, and a lot of times offensive, garbage.

Don't get me wrong, I love that we can share ideas and speak openly on Reddit, but I don't really feel that someone telling multiple people to kill themselves is helping Reddit very much.
TL;DR: 
In my opinion, Reddit would be a much nicer place if we added something to filter users who only post negative, offensive, harmful, and useless comments.