At my first job right out of college, me and another guy (who would eventually become a really good friend) were hired about the same time. He had hair down to his shoulders and an earring. I was clean-cut. Office environment.
He was the better worker, tried harder, more efficient, everything. And I was kind of a trainwreck. Didn't matter. He got drug tested 4 times in the first year. I never did. He eventually complained to HR about it and they backed him, but he ended up cutting the hair anyway and said people started treating him a lot differently after that.
Hairism? Social injustice. Something must be done.