Well,I believe that everyone judges others by their appearance,and those who deny that are either hypocrites or simply wrong.
Unfortunately,presumptions about others are totally unavaidable no matter how mych effeort we put in trying to follow the old good saying "Don't judge the book by its cover" and be open-minded.
I don't claim here,that producing opinins about the others basing solely on their looks means that we pay attention to brands of clothes or whether some ne is beautiful or not,although this definitely happens as well.
Judging might be a bad word here,though,but if we are careful observers,we can draw certain conclusions and learn a lot by looking at a person.
First of all,facial features reaveal knowledge about the particular individual.The face of a person who smiles a lot,and this is a sincere smile differs substantially from the face of a person who is sullen.And basing on the frequency of smiling and laughing certain character traits can well be determined.Secondly,if a person reads a lot and has some intellecttual effort it also shows in one face,as special muscles are used,so it is pure anatomy,isn't it?
The next thing are clothes.And I don;t say here that we' re given the right to infer whther some way of dressing is decent/fashionalbe or the oposite,but we do learn a lot about people by looking at theior clothes.
For instance,unusual attire,can mean that the person is creative and/or wants to stick out form the crowd,which means that they don;t take too much notice of what the others might say.If a person wears conventional clothes that everybody else wears,it might mean such a person has quite a conventional life and praises traditional values,and meybe is even a bit of a conformist,as they are afraid of shoking others.Etc.
Finally,as far as clothes are concerned,with young people,we can make out what sort of music those poeple listen to,and what interests they have,and/or what subculture they belong to.
The obvious thing is,that we sunconsciously serach for people who are somehow similar to us.And the way they dress,move,speak,look ect.are elements indicating whther we like that particular person or not.