Assault On Free Speech

[A Theist]

What you're asking is not just a simple yes or no question. In the legal sense Chick-fil-A broke no laws. To your first question, the business owner is a private citizen who has every right to his opinions. If citizens don't like the business owners positions they can take their money elsewhere. Public office holders are entitled to their personal opinions as well but their first obligations are to provide equal protection under the law to everyone without bias. As far as what's ethical, it depends on which side of the issue you're on. Wouldn't you agree? No to both questions.

I did not ask if any laws were broken. I did not ask what the customers can do in response. I did not ask what the obligations of public office holders are.
None of these have anything to do with the business ethics of Chick-fil-A in its conduct.

"Is it not a severe violation of the obligation between supplier and consumer to provide an unbiased service to a market in demand of it?"
"Does this conduct not qualify as severely unethical?"

Your answer to both questions is no. This implies you do not believe their actions to have been biased, a violation of trust or unethical.
Fair enough, by that logic I assume you wouldn't mind a privately owned business very vocally promoting homosexuality moving into your neighbourhood then?

I lived in a Urban inner city neighborhood for the most of my lifetime. There were a lot of gay bookstores and gay businesses which pandered to the gay lifestyle that moved in to our area over the course of some years. They weren't breaking any city ordinances as far as I could see and there wasn't an effort by our mayor and other elected office holders to ban gay businesses from our city like Chicago and Boston tried to do Chick-fil-A.
Do you think the mayors of Boston and Chicago severely violated the trust of their office when they tried to deny a businessowner his rights because of political and religious differences? Doesn't their conduct also qualify as severely unethical?