[seqastian]

They can sell ads better if they know where you are. Wifi data is making that every easy and battery saving to track.

[Youden]

They already know where you are to a sufficiently high degree of precision with GPS. The battery matters to you, not to Google. Wifi ads next to nothing for Google.

[iszomer]

Or more pedantically, Google knows where your device is to a sufficiently high degree of precision. They can't stop me from just leaving that shit home or in a faraday cage.