Why does the app need Bluetooth or WiFi scanning permissions? Can't you handle the pairing in the OS and allow the app to use an already established connection?
I think for Bluetooth it doesn't work that way (you can connect some standard devices Android can use itself, e.g. a headset on OS level, but not arbitrary devices). For WLAN it's probably an ease of use thing, automatically finding and setting up the device instead of telling the user "please connect to the WLAN created by your new device and then press this Button".
