I agree it's America & you can do what you want or at least we like to think so.
Is the sign against the law? Probably, so then is there a smarter way to go about this than putting that sign in his front yard & gain his intended goal? Yeah, I tend to believe there is a smarter way to go about this.
Kinda like those bakers who keep landing in court.
I've ran several businesses over the years and for some customers I was hard to deal with, even to the extent of being impossible and they chose not to deal with me which was my intended goal. What can I say, I don't care for some people & that's life. Others, I just decided immediately they were not the customer for me. My descisions weren't really based on race or religion as much of the fact I have a gift of figuring out if you're an entitled crap head rather quickly. I was running a business and as far as I was concerned owed any potential customer nothing until they placed an order. If I thought they would be problematic then the sale probably became more difficult for me to make intentionally. I ran successful businesses & part of that responsibility is for me to minimize my liability. By being cautious on who I decided to work for I believe that my net profit increased as a result of my choices. Again all my viewpoint take it or leave it.
More than one way to skin a cat as they say and this guy is looking for a fight obviously. Why not just walk to the local watering hole, it'll probably be cheaper and less expensive?
Not an intelligent way to go about this in my opinion. I appreciate his service non the less & am grateful. I hope this works out for him.
Matthew 10:16 comes to mind.....