CHA isn't just for looks, and the same can be said of any helmet object, since helmets would obscure faces a lot more than hoods would.
If anything the hood allows more of one's face to be seen than not, and it's pretty much been established that hoods are not perfect disguises.
CHA is as much in how one conducts oneself as in their outward appearance. Call it a personal "presence". It's the quality of great leaders and such that goes beyond physical beauty.