The way I look at it is, assuming you don't hold a monopoly on a particular service, you can choose not to do business with certain people, for whatever (legal) reason.
However, it cuts both ways: your other customers also have the option to boycott you and encourage other people to do the same.
And if every business decides to stop doing business with certain people, then either a) those people really need to rethink what they want to do, because maybe everyone else thinks they're reprehensible, or b) we actually do have a case of a civil rights violation in a new way that we haven't considered making a law for.
Every business deciding not to serve black people would be a case of (b) (though retrograde, as we already have laws around that), and refusing to provide service to hate groups is, IMO, clearly (a).
However, it cuts both ways: your other customers also have the option to boycott you and encourage other people to do the same.
And if every business decides to stop doing business with certain people, then either a) those people really need to rethink what they want to do, because maybe everyone else thinks they're reprehensible, or b) we actually do have a case of a civil rights violation in a new way that we haven't considered making a law for.
Every business deciding not to serve black people would be a case of (b) (though retrograde, as we already have laws around that), and refusing to provide service to hate groups is, IMO, clearly (a).