That aside, to use the classic stick reserved for complaining conservatives, it's a private company and venue and they have a right to choose who they want in there.
But beyond those points, we already make distinctions between private spaces and spaces open to the public that happen to be privately owned. When you invite in the public you waive some of your rights to free association. I see no reason why we can’t add further restrictions beyond the currently protected classes.
If you want to build a completely privately funded members only stadium, have at it.
And it depends on whether the ticket holder can prove they suffered damages beyond the cost of the ticket. Or whether a group of people in a class action lawsuit can do so.
At least one law firm has already successfully sued to overturn their ban.