...I think that firing/not hiring someone because of the way they choose to appear is legitimate. They made their choice and must accept that it can cost them. See NobodysHome's comment - through his personal experience he expressed that sentiment far better than I did.
That sounds too close to excusing ill treatment solely on how someone is dressed or appears... they choose not to fit societal norms, so they deserve what comes their way? Cops harassing people based solely on punk haircuts and leathers, or fitting a certain racial profile, is lazy incompetent police work.