The Seahawks are in second place in the NFC West with a decent shot at overtaking the 49ers for first place by the end of the year. Philadelphia is in second place in the NFC East with a decent chance of beating at the Cowboys for first place. The difference is what happens if Seattle loses as opposed to the Eagles.
Philadelphia is 5-5 and a loss would make their hopes of making the playoffs much dimmer. Seattle is 8-2 and while a loss might hurt their chances at winning their division, a loss would not eliminate Seattle from the playoffs.