Is Dreadlock Discrimination Race Discrimination?

In a recent case, an African-American woman was offered a job as a customer service phone representative—on the condition that she cut off her dreadlocks. She refused. 
The employer said it was a race-neutral grooming policy. 
She said it was race discrimination.

Where did the term dreadlock come from? The woman’s attorneys said that dreadlocks were closely tied to racial identity, including this cultural connection: “During the forced transportation of Africans across the ocean, their hair became matted with blood, feces, urine, sweat, tears, and dirt. Upon observing them, some slave traders referred to the slaves’ hair as ‘dreadful,’” and dreadlock became a “commonly used word to refer to the locks that had formed during the slaves’ long trips across the ocean.”

The federal appeals court said that Title VII--, the nation’s main race discrimination law for employment— defines race in terms of immutable traits, not cultural traits associated or identified with a race.

The court in question is the Fifth Circuit Court of Appeals (Texas, Louisiana, and Mississippi), a court that usually has a conservative take on discrimination laws.

The Seventh Circuit (Illinois, Wisconsin, Indiana) has a broader definition of race. That case involved an African-American woman who was denied a promotion due to her natural Afro. 

My frustration with the court ruling? It was very expansive, delving into the definition and meaning of "race"-- but my question is what is the business justification for a grooming policy where the job is a phone representative? There is no valid justification, which makes it seem like race discrimination.
For more, click here: http://media.ca11.uscourts.gov/opinions/pub/files/201413482.pdf.