Good point. That makes them a “public accomodation”, so we’ve been told, so the laws are different as applied. So, that should especially apply to a virtual monopoly such as Facebook is.
I see these arguments a lot about Facebook, but I haven’t seen anyone present a single example of either the public accommodations provisions of the civil rights act applied against websites, or provide an example of a website being judged a monopoly and subject to regulation as a public utility.
If there are no such precedents, then these argument seem like just a bunch of special pleading, “these laws don’t apply to anything else on the internet, but they should apply to Facebook because they’re our enemies!”