Remember when a sign posted in a business stating “We Reserve The Right To Refuse Service To Anyone” actually meant that? And you could “get away with it”?
In reality, that hasn't been true since we the government banished the right of free association in 1964. Once the Civil Rights Act introduced a new government power-- the power to nominate classes with extraordinary legal protections, it was just a matter of time before more and more politically motivated protected classes were added that meant you could refuse the right to service non-protected classes, but if you refused service to a protected class they would own your business.