Did you read the post? The women interview without head scarves and then wear one to work. This actually happened in a very upscale NYC department store.
The only way around it is to ban all head coverings, but maybe they are afraid of being sued for that!
In that case, don’t hire anyone who even remotely looks Arab.
And yet one of the restaurant managers mentioned that a hijab would be a problem on the job. Why? He would have been better off keeping his mouth shut on the subject. Which I believe was dfwgator's point.