Just to play devil's advocate:
I would agree if the Ranger's Favored Enemy bonus was a (SU) or (SP) ability, but it's not, it's (EX). What if we throw the ranger's ability Quarry (EX) into the mix, it says:
"A ranger can have no more than one quarry at a time and the creature’s type must correspond to one of his favored enemy types."
So, does that mean that a ranger (without making a check) automatically knows what type of creature he's fighting? No other character can do that. Now some creatures are easy (Oh look, it's Zombie Bob again) but if it's a unique or even a rare creature, how does the ranger know? Does he just try it and hope for the best?
If a ranger has Favored Enemy Outsider (Eeevil) but he can't identify and evil outsider to save his life, why would he know to shoot or stab slightly to the left to maximize his damage potential?
Again, just curious.