It's not the role of sociopaths to be accepted by society. On the contrary. It's a lonely path, a sort of left hand path. They are the dragons who kidnap the princess. The beast, the lurking fear.
Than again, I don't think there's a lot of them whom know that implication. They just follow their inner beast by instinct, or basic interest. Than again, the majority of people does it all the time, not really knowing what they do.
To be bref, they are a reminder that life in this universe is bref and impermanent, and that we all gonna die in a way or another, and that life is based on taking something from another to be able to continue to strive. In an ideal society, we wouldn't need them to remind us of that, but in a insane and myopic world, maybe we don't have the choice to have them to shake the things up a bit.