Donald Draper wrote:
Lets see different skin colors, clothing, hairstyles. Some with piercings and only a few with facial hair. I am not convinced they all are the same species or live on the same planet.
Trek has always indulged in a casual kind of racial stereotyping with its aliens. Early on I think it was a matter of being able to afford only a few makeup and costuming cues to indicate difference from human beings. Over time, as the Franchise gave up all pretense of treating alien species as other than representing human national/ethnic differences the whole "they all look alike/dress alike/act alike" thing got really annoying.