So at what point does a private business become a &#x27;common carrier&#x27;?  Because pretty much everyone agrees a business can chuck someone off the premises for just about any reason, and most internet forums and communities end up being more about &#x27;what the owner wants to allow&#x27; rather than anything else.<p>Do you suddenly lose the right to tell people what they&#x27;re allowed to say or do if your community becomes popular?  How about if it&#x27;s the leading resource in a field of study, or half the population end up using it?<p>Because this is what&#x27;s bugging me about these arguments.  Why can a community like a forum, mailing list, Usenet group, Slack group or subreddit choose what people can say and block comments for any reason, but say, Facebook gets criticised for the same thing?  They&#x27;re all communities, they&#x27;re all privately owned...