Seattle needed both time and possessions that late in the game. If Bostick doesn't fuck up it is game over. It was OK from the Packers point of view to give an extra possession. Bostick gave them the extra extra possession them need. Plus the fucking 2 point conversion fiasco that should have never happened.
So in summary, the Packers gave Seattle an extra possession and 2 points more than they should have using the run-run-run method correctly as they did.