Given that most people will use their one and only router for this, it means most of these devices will have access to the internet. Sure, you _might_ be able to prevent it if you jump through hoops (because it really is annoying to setup a second wifi network, at least in my experience) and assuming the devices don't fail if they can't phone home (and we can be sure some will). But everyone is much safer overall if the "common standard used by most people" did not use wifi.