It has nothing there when it rolls out of the factory. There is no such thing as a factory hugger. Just tire and undertail/rear fender.
Any dirt, rocks, muddy water, road salt, etc that gets flung up hits your factory undertail which then gets scarred up and gouged by it, which since it's not visible and started life out ugly to begin with doesn't really matter.

However, since everyone either chops off the rear fender and exposes the undertail to view, or mods in a pretty painted undertail all that dirt and debris that's flung up (at considerable speed and force I might add) collides with either your shiny new, painted undertail, or your taillight and rear fairing paint, doing a decent amount of damage to the less durable surfaces (paint). A hugger directs rocks, debris and water out to the rear and away from the pretty painted parts of your bike. Doesn't sound very pointless to me.

However I do agree that they don't add anything to the bikes appearance, in my opinon, they look kinda lame. But pointless? Please, thats like saying your front fender is pointless, it serves the exact same function for the front of the bike. For the record, I have a hugger on mine. Like the bike better without it, but it serves a purpose so I leave it on.

You may live in some pristine part of the country where everything is pavement, and always kept perfectly clean, great for you. Most of the rest of us deal with imperfect roads, and for us, they really help alot. Most newer bikes come with them stock now, btw. Though the new ones are a lot sleeker.