Individual Universities are listed because of their depth of accessible online resources and lateral connectivity. Also, although there is an extensive list of Libraries on the "Search: Part I" page, the Universities linked to the Web have extensive library facilities and services of their own, some of which are open to the public.
I would surmise that all State Universities would allow online library privileges to non-affiliated ISPs, at least those residing in the state in question. And if not, why not?