My friends and I went as a group of three male and three female Asians. We are all well mannered and conservative 20-somethings.
As soon as we stepped onto the premises, the waitress tried to discourage us from even sitting down. She mentioned a few times that there were no tables except for the one table that was literally right in front of us on the patio.
She did not help us set up the table, was very unfriendly and very un-helpful.
She tried to discourage us from even eating and made several comments, repeating herself vigorously within a span of 5 minutes. Her comments were so blatant that one of our party actually said, "So, are you trying to tell us not to eat here?" It was at that point that we decided to leave and we took our business elsewhere(Louis II btw, it was VERY good. TRY THE GRAVY!!)
So, all you Non-Caucasian visitors to Huntsville, beware of the prejudice stemming from The Navigation Diner Co.