I hate it too, but there is something about eating with your mouth open that makes the act of eating more enjoyable, because you actually chew your food more than you would with your mouth closed. At least I do. Still, that crap bothers me. And whenever that Geico commercial with the upside-down mouth, chewing food comes on, I have to mute it because the noise is simply aggravating. Yes, that commercial gets to me.