Well what is private and what is public? there are plenty of private organizations that are function as public institutions.. i think of musuems, or gardens.. some of these quasi public places are free, and some require a paid admission.. some offer membership, and some are fully public.
the same goes for many of the plazas that exist in NYC, and other cities.. or the indoor covered sidewalks -- or malls.. are they public or private? and even public places.. like city schools aren't really open to the public.. you need to sign in, and have a reason to be there.
Yes, it is a public places.. but somewhere, there is a server, and a hard ware administrator, and electric bills, and back up tapes, and new copies of anti virus software, and the sortware that run the whole board. All of that is bought and paid for, and not by me, or you, or generally speaking by anyone here anyone! (but its nice to give donations, and Anu has asked.) so a good deal of what we see as a public places, is only public because of Anu's good will. and he has asked for donations.. he hasn't sold us stock! we aren't owners here, we are guests!
its easy to forget.. and to just think of it as fully public! Anu could pull the plug tomorrow, and this space could disappear!