Because not having the bye is an inherent obstacle, but won't be once they're out of the round (especially if they sweep which also changes their rotation). Plus lines change all the time based on gambling action and perception.
Had the Reds won last night Phillies odds might have changed too (given the six has won in the NL every year), and probably would if Reds advance.
Now that we are actually here I think I can say I wish they'd gotten the 1 seed and avoided LA. Playing the defending champions and an overall juggernaut, even after a down season, in a short series, is a tough draw. I'm not so sure Phillies will be favored in it either (though if they were it will only be because of home field).
