Does calling for the rescission of laws banning private discrimination make a moral statement in support of bigotry? Hardly. But the question implies just such an accusation. In doing so, the accuser reveals his own intellectual cowardice and bankruptcy by evading the philosophic issues involved, and resorting instead to the tactic of ad hominem.
Nonetheless, the charge should be answered.
Calling for repeal of anti-discrimination laws does not imply support for irrational, bigoted, or evil forms of discrimination, such as racial or gender discrimination. Nor does it imply a government legal sanction of same. Laws that protect rights don't sanction any particular type of behavior, good, bad, or otherwise. They sanction the individual's freedom to act on his own convictions and judgement.
Here are a few analogies to make the point. Does protecting freedom of speech imply that the law sanctions Nazism just because it protects a Nazi's right to speak in favor of Nazism. Or, does protecting property rights imply that the law sanctions the criminal's use of his property to plan and execute a bank robbery? Or, does protecting freedom of religion imply that the law sanctions a fanatically religious parent's reliance on faith healing rather than medical treatment for his gravely ill child? The idea that protecting basic rights sanctions all possible bad or immoral behavior associated with that right, if accepted and consistently applied, negates all rights, and any possible freedom along with it. Since freedom doesn't guarantee that everyone will act rationally or morally at all times, no rights are possible under that premise.
But by protecting a bigot's right to freedom of association in regard to sexual orientation, race, or other form of immorality, the government does not sanction his behavior. Of course, the government should step in if actions associated with one's convictions violate rights, as in the case of the bank robber; or if the Nazi actively plots the overthrow of the government in order to install a totalitarian state; or if an anti-gay marriage religionist physically assaults a gay couple because they are a gay couple.
When the government protects rights, it assumes neutrality in regard to the moral propriety of the exercise of those rights. It simply protects the rights of all people to act on their own convictions. Surely, some have irrational convictions. But if one person's right to act, including the most irrational person, is violated, all people's rights are threatened.
In the case of association according to one's convictions, the threat is indeed extensive. Why? Because if the government can dictate who you must associate with, it has effectively arrogated to itself the power to dictate what convictions may properly guide your actions; i.e., what beliefs are to be permitted. This is a wide-ranging threat not just to religious freedom but to intellectual freedom generally. Since action is the means by which the individual implements and realizes his convictions and values, the right to live by his own judgement—his right to his own life—is thereby infringed.
But the government would only ban bad ideas and convictions? That's precisely the point: How does one define "bad?" By whose standard? No government official should ever have the power to dictate good vs. bad ideas. Its only job is to proscribe rights-violating actions. Government should not become the arbiter of ideas—we should not have a ministry of truth—or limit individual actions resulting from those ideas, until and unless those actions violate others' rights to act on their ideas. Private discrimination violates no one's rights. It should not be illegal. Repeal those laws, and the restoration of full religious freedom for social conservatives follows.
Protecting Rights vs. Sanctioning Action