Deans and getting in trouble

Why is it that students that are never in trouble and are straight A/B students get dress coded for something so simple as not long enough shorts but students that are always in trouble and never go to class, are always out of dress code hang around deans and still don’t get in trouble? I think that our deans have favorites and aren’t afraid to let everyone know? If your gonna dress code one person you mind as well dress code them all.