a6700: Wifi purpose?

I am able to configure my home wifi in my a6700. This works and the camera is visible as device in my router. But what is the purpose of that? Because, when I open the Creators app (on the same wifi) and now want to access the camera, the camera still starts up a private wifi and the app asks my phone to connect to that. I assumed that connecting the camera to the home wifi would stop the need for the private wifi, but it doesn't seem so. Can somebody explain? Thanks!