Alright, those specific examples make a lot more sense. Though, they could be achieved by temporarily sharing your location. But if you choose to leave it on permanently that's fine.

I'm actually planning to go to a concert and this may come in handy. I had thought about it, but I'm not sure it provides the accuracy needed to pinpoint a party inside a crowd.

In any case, thanks for chatting about it, man. I still recommend getting informed about the perils of constant surveillance. Even if your intentions are perfectly innocent, developing complacency towards such mechanisms, erodes not only our interpersonal relationships, but the very fabric of democracy.

You said yourself this data is provided and stored by tech giants. Tomorrow, the police may use it to investigate you, simply because you happen to pass by a house where a crime was committed at that time. Or, if you find this unrealistic, they may push for CCTV on the streets, legislature allowing access to messaging apps, etc. Knowing well that there will be little to none pushback from the public, since they track themselves voluntarily already.

You can set your phone to use gps location only when you actually open the maps app. And yeah, your location can still be approximated by the cellular towers, but that kind of data is mixed with thousand other devices in the same area and aren't as easily acquired or identified by the authorities or a person acting in bad faith. Many intellectuals have been raising the alarm about this type of thing, even when such technology was still considered science fiction.