It's good to see someone understands this. It's unfortunate that many people will only apply this when it is in terms of liberals being able to disassociate from people on the right, but won't apply it to a baker or photographer who doesn't want to participate in a ceremony they believe to be sacrilegious.
I agree with the thrust of what you're saying, but I'm going to add two caveats.
First, companies are legal fictions, created through government regulation. They do not have the same rights that people do. In return for government benefits (e.g. limited liability), you agree to play by the government's rules.
Secondly, professionals are bound by professional ethics which may conflict with their personal rights to the point where the only solution may be to find a different job. So I have less of a problem with a sole trader photographer refusing to participate in a ceremony they disapprove of (which, I might add, could be as simple as saying "can't do it that day") than I do with a pharmacist refusing to dispense birth control.
And as always, freedom of speech and freedom of association does not imply freedom from consequences.