You made an analogy with zero applicability to the topic. I'm sure it sounded clever inside your head, but it was pretty stupid. Feel free to prove otherwise.
If I understand him correctly, he made an analogy with 100 percent applicability to the topical point he was making. The frequent claim that some choices are immoral because 'it's discrimination' is not especially useful. Making any choice in life always involves discriminating. And any interaction with another human being necessarily involves choice. That you and I decide to participate in this thread, and not some other, is a choice...discriminating between who we wish to engage and on what subjects.
But in a free society, persons (absent third party impositions) decide how they will interact...each member as "self-owners" having the right to their own holdings, but not other's holdings, unless acquired through voluntary means.
So, right or wrong, anti-discrimination laws are an imposition of involuntary choices by a third party, telling buyers and sellers who must buy or sell to, and under what criteria. They don't ban discrimination, they redistribute the rights to discriminate and make choices for buyer and seller - they impose involuntary transactions. Buyer and seller are not "equally protected" in their liberty because the whole point of such laws is to restrict the liberty of free choice on behalf of one party over another.
Finally, so-called 'protected groups' (beneficiaries of restricted liberty) are arbitrarily defined. In public accommodation 0eople are not protected on the basis of their looks, dress, hygiene, skill sets, accent, union affiliation, class, drug use, hobbies, interests, or health (including mental health). And in most states they are not protected on the basis of political beliefs or sexual orientation, credit history, or sexual habits.
There is nothing wrong with discrimination per se', so what justifies anti-discrimination laws that restrict free choice? Of what business is it of the state who I buy or sell to? If I don't like vets (who promote war) or the KKK 'christians', of what business of yours if I choose not to sell to them?