Re: Why ?
because if you turn on your Bluetooth for headphones apps _can_ track your location, no matter what settings you have. Google is trying to tell you that turning on Bluetooth necessarily reveals your location and there is nothing they can do about it. It's not their fault that Bluetooth is a wireless protocol that enables store to track you. You need to OK that for apps you trust.
Sounds like you _have_ been using Bluetooth without realising the consequences.