Radio City Music Hall is a private venue, they can ban or exclude anyone they want, as long as it's not due to membership in a protected class. You don't have a right to attend a Rockettes show, and if she doesn't like this policy she can start her own Christmas Spectacular show.
While in principle I'm inclined to agree, I'm not sure I want to live in a world where you might get yanked from a business after paying for entry because your employer is deemed to be adversarial. This has a nasty tinge of a cyberpunk dystopia. It fells at best illiberal, in the classical sense it like a kind of techno-mercantilism.