Air-Stream Wireless is not a WISP but some Internet Service Providers (ISP) do sell Internet access over wireless these companies are known as a Wireless Internet Service Providers (WISP) and often use identical equipment and share the same radio frequencies used by Air-Stream.
A WISP offers a connection to the Internet, they are not a Wide Area Network (WAN) nor are they structured like an Open Access Network (OAN). They are managed and financed in quite a different way compared to Air-Stream Wireless and should not be seen as anything other than a gateway to an Internet connection.
A WISP is a Business and must keep track of users in order to provide different service packages, they are also legally required to guarantee continuity of services and as a business need to bill customers for this.
For more information about Internet Access on the Air-Stream Wireless Network see: Network Content – Internet