Just a thought. If a man goes and does a robbery with a mask on, and the police walk up to him and ask Are you black? Statistics just because an Indian calls you doesn't always make them a scammer. Do you ask if they are Indian? It's flawed. All of it.
He should sue the establishment for not stopping the harassment. Maybe next time someone throws a fit the restaurant will end it instead of letting it go.
Let's say, bless her heart, as irritated as she was if the staff would've de escalated and said something to her then she would've likely got mad and left or got mad a ranted to her Facebook friends how unfair they were. It's a private business has nothing to do with free speech. Has all to do with common sense. De escalate the situation if not then you ask them nicely to leave.