Is the superbowl unfair because the Packers have to win 4 games & the Steelers only 3?

That is the way the playoffs are set up. The Packers were seeded #6 in their conference and the Steelers were #2 in theirs. The Steelers earned their first round bye earning one of the top two seeds in the playoffs. The Packers were lucky enough to get into the playoffs. If the Giants had won their last playoff game, the Packers would have been eliminated after week 17. They most definately wouldn't have been in a position to play for a Super Bowl.