I hope she's set up a legal defense fund, for she is going to need it. Her range is open to the public. Banning people for religious reasons is as pernicious (and as illegal) as putting up a "No Irish" sign.
My FOB ancestors, some of whom I knew before they passed, were mainly anti-Catholic. They were that way because, back in the Old Country, the local peasantry would, from time to time, get liquored up and go an a pogrom. Pogroms were when the good G-d-fearing Christians would engage in acts of rape, pillaging, arson and murder against the local Jewish population. When I was a child, one of my great-aunts advised me: "When it's time for you to marry, better you bring home a Schvartzer than a Catholic."
Clearly, they considered Catholicism, if not Christianity itself, as a religion that held acts of violence as part of its tenents. So, let's say, for the sake of argument, that they opened up a business that served the public. Would they have been entitled to put a sign on the door that said "No Catholics"?