Different rules? Why? It is a public company in the private sector. "Free markets." Why should its operating policies be any different just because it is widely held?
You'll have to ask the U.S. government and the SEC that question, but I think the main difference centers around disclosure. Public companies have to publicly disclose far more than private. Presumably there are good reasons. One rule that is apparently the same though is that if you are open to the public to do business then you can't discriminate among your customers on the basis of certain customer characteristics specifically defined in law. And that rule holds for both privately held businesses and publicly held ones. It's been the basis of a number of disputes in recent years. Suppose you're a devote fundamentalist Christian and you own a barbershop lock stock and barrel. A guy walks into your shop wearing a Tee Shirt that says "I'm an Proud Infidel". According to the law you have to find some other, legal, basis to kick him out other than his Tee Shirt Message. Or, as a practical solution to your dilemma, you can cut his hair, but give him an unasked for Mohawk. These laws are hard to enforce.
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I guess my point that I was so ineptly attempting to make when Tsing posted: "Youtube is a private company, and should be able to do ban whomever they please, for whatever they please" ... and I pointed out that they are
not a private company, was that they had to follow certain rules regardless of whether they were a private company or not. (a point I cleverly failed to properly make.) These would be the rules that all businesses, regardless of whether they are public or private, are supposed to follow
if they do business with the general public. Ergo, Facebook can
not do as the like in every instance. But Tsing said "should" not "can", and so he was expressing his personal opinion, which in this case is at odds with the government's position, and incidentally with my own too. I don't think private companies should be able to do whatever they want if they do business with the general public. And in fact, they can't legally. Said yet another way, there are certain matters with regard to how a company does business with the general public that do not hinge on whether the company is private or public.