When will people ever use "I don't care" in it's actual meaning? When you don't care about something, you feel indifferent about it = no opinion. According to the many who use it, it's more of like "Urrgh I'm upset what others think of me but I don't want to admit it". I'm not trolling here, but it's really the way I see how people use it in arguments, it doesn't wrap up anything.
I know this post is rather off-topic, but I've been wanting to say this for a long time.