The simple reason for this is that we are all already sharing our locations with many corporations all of the time. I just shared my location with home depot a few days ago so it could locate which store I am in. Google knows my location constantly. There is an urgent, obvious need for us to develop social practices around location sharing. We must build these practices and preferences within our communities so that as the wide scale tracking develops we can understand what we would consider reasonable. The demarcation of pen registers to track phone calls came out of a sense of what is a reasonable invasion of privacy - we must socially develop that sense around this form of sensing.
I now have a pretty healthy community of location sharing and the stories in this piece are familiar. When I was in the ICU for a few days (thankfully due to medical confusion and not a real condition) people reached out to see if I was ok and needed anything. I know people who discovered that a mutual friend died unexpectedly when their phone had been at the morgue for several days. There is no question, in my mind, that "always on" sharing is probably too much for most people. But the only way we will develop a detailed sense of what we want instead (and what we should insist on when it comes to corporate tracking) is to engage with it and reflect.
So far my thoughts on how to do it better involve a series of contextual elements to increase or decrease the specificity of sharing. I.e. if you are out doing errands there's no need for a precise location - show a few blocks. However, if you are close to a friend, show a precise location and notify both parties. Consider creating tiers of sharing where when you enter an area of concern (hospital, morgue, etc) your location is visible and flagged for people close to you but otherwise appears generally to others (as if you are shopping as above). Etc, etc. There is much work to do here and I hope others are thinking about how to do it.