Originally Posted by
Segev
They have value as means of establishing whether you can trust somebody to share a particular set of morals or ethics. Yes, you CAN trust that a Lawful Good person isn't going to backstab you, but will deal reasonably with you and tell you if there's a conflict of interest they perceive. Yes, you CAN legitimately worry that the Neutral Evil person might kill you in your sleep; it's certainly within his moral and ethical capacity. And as "team jerseys" that are not so much donned and doffed by applying the label, but rather are endemic parts of the creature's being based on the person they are, they work just fine.
You can have your exceptions, if you want them, but they are just that: exceptions. And they're "the evil guy who works with good guys," not, "the good guy who proves that good doesn't actually mean good."