FYI
Bergeron +6, Richards -2, Zetterberg +12, Hossa +24, J. Staal +19
so besides turn-over machine Hossa, Staal has a better +- then everybody else you mentioned. But wait plus/minus is not everything, what about Staals 50+ points getting 3rd line minutes. Or maybe that cup ring he's got over Bergeron, Richards, and Hossa. Or maybe it's his 358 consecutive games he's played. No you're right he is overrated and doesn't deserve the nomination.
Find me a player with better plus/minus, more points, in the same amount of average ice-time. Oh wait, I bet you can't becuase there isn't any.