While quite a few users will use services on their home lan, contrary to the parent posters statement, I believe the majority of users don't use those services

While quite a few users will use services on their home lan, contrary to the parent posters statement, I believe the majority of users don't use those services via a web browser. For instance (to draw from your examples): 1) Most people either install the printer drivers from the manufacture's web site, or let Windows/OSX auto-discover and auto configure the printer with out a web browser. 2) Most users just use the wifi information provided by the cable/DSL provider when they installed the modem, use the WPS button, or install the app that came with their router rather than use a web browser to configure it. 3) Most users will not tether their computer to their phone. 4) Most don't install a DVR app on their phone. If they did, their phone probably communicates with their DVR via some intermediate cloud service. 5) If their receiver auto-connects to their itunes library, it probably won't complain about that itunes not having a public certificate either.