I have to be honest and agree that looks do matter in certain types of jobs. May be shit and a lot of qualified and great workers get turned away because of it, but bottom line is, we all prefer someone well groomed and relatively "standard" (as in no distracting and very personal ornaments - that say, "look at me, aren't I different" -, and a just generally pleasing looking, clean person...someone approachable). The truth is though that many employers will hire people with "above average beauty" because a) it makes office scenery more pleasant, b) the customers come in more often to look at that person and may buy more often as a result.
I also think that sometimes you can get an overly beautiful sales person, and that's intimidating to some. Or sometimes these beautiful people are rather stuck up towards less beautiful people (appearance-wise) and look down at you, completely killing the "beauty attraction factor".
So shoot me. Appearances matter sometimes. I'd much rather be honest than be PC.
edit - just to add something more...I think subconsciously people have this thing whereas if they buy from a nice shop where beautiful well-dressed people work, you think maybe it'll rub off on you. It's silly but on many levels we are still very primal. But it has to be said that you can so easily warm to someone who's not so perfect in terms of appearance, if they have the right sales pitch, smile, attitude. It's not all in the looks...of course!!