Those restrictions are also infringements on the rights of a private property owner who happens to operate a business. Do you think additional infringements are OK, as long as you agree with them? I don't. Wrong is wrong.
And as I posted, if you think the 2A (which was intended to restrict the government, not individuals) allows you to exercise those rights on my property against my wishes, what of my counter example of holding a political rally on your business' property? Is not that a restriction of my 1A rights? Is that then allowed by virtue of the same argument?
The law of the land is that businesses cannot prohibit women, Italians and democrats from employment or from entering their parking lots, and that is not going to change in the foreseeable future no matter how loud you scream about it.
You are advocating for firearms to be restricted in ways that other "rights" that are not enumerated in the Constitution are not restricted. The Supreme Court held in McDonald v. Chicago
that the Second Amendment cannot be relegated to a second class right, subject to an entirely different body of rules than the other Bill of Rights guarantees.
When we advocate for parking lot carry, we are just asking the government to follow the Constitution as it has been interpreted by the Supreme Court. You are advocating for something other than the government that we have. Would you advocate for a government that can make a law that allows an employer to order their employees not to resist being beaten or raped, i.e., to refrain from self-defense? The framers of our nation did not distinguish between the right to self-defense and the right to use arms. Do you think they were wrong?
And holding a political rally is not the same thing as someone who has a tool of self-defense in their private car.