You beat me to it. After I posted then the same thought hit me. Just where are the court rulings stating that a private business has now become public.
Good question!
I'd guess some socialist judge in the 1930s, in an effort to destroy common law that regulates private property, ruled that any business that accomodates the general public is a public place and may be regulated by government. That, of course, is absurd as it nullifies hundreds of years of private property rulings.
Look, for example, at businesses that discriminate against the public.
There are realty companies that will not show you certain homes unless you can prove you're financially able to purchase such property.
We see exclusive businesses, such as high end jewelry stores, that post a sign on the door "By appointment only." And you won't get in unless the management approves of you.
Night clubs in big cities post bouncers at the door and allow in only "beautiful people."
I'd say businesses such as these are clearly not open to the general public, yet government wants to consider them "public places." I don't think so.