Replying to Karma krucifiction

So I was thinking about the Karma thingymagiger...

I don't get it. What is the point exactly? Who is using it to rate people right now?
I think it is a pretty neet concept, and could be used for alot of different things on the site. But right now I don't see the point. I read the page on it, and how it would benefit the site because of spamming and over posting and shit. But I don't see that happening really. I post way too much, but its just cause I have lots of opinions.

I don't like the fact that if someone doesn't like what you say they can rate you poorly. It's kind of like you have to watch what you say. Think about all the global warming and no poles threads, some people have very good points on both sides, and because someone doesn't agree with them they can give them a shitty karma over an over? Do I understand this correctly or no?

 If I say something retarded, or anyone else for that matter, you should be held accountable... but to what ends? If you tell a mod to eat shit, you're probably going to get banned, but if you're having a debate over something intelligent and get a whole bunch of shitty karma... is it game over too?

I just wanna know.