Take a look at your wallet. You'll find this:
"STEEM POWER
Steem Power, influence tokens that earn more power for holding long term and voting on posts. The more one holds the more one can influence other’s rewards and earn rewards for accurate voting."
And that's the point.
Ah. so it magnifies your rewards. got it.
Yeah, it does. Although I'm sure it will benefit you in other ways too.