I used to work on combo bluetooth/fm/wifi chips that are used in cell phone applications. There is additional cost to make it work, both for bill of materials

I used to work on combo bluetooth/fm/wifi chips that are used in cell phone applications. There is additional cost to make it work, both for bill of materials as well as recurring and non-recurring testing. So many customers preferred only to use the bluetooth/wifi portion of the chip. We even had a FM TX version in some chips.