It would certainly be detrimental if your boss decided to check up on you on your day off and discovered you were at a competitor's office -- kind of suggests you're looking at other employment.
Well yes that would be majorly detrimental to my boss. I on the other hand would benefit greatly from the resulting payout.
Or something less drastic: If McDonald's notices you're close to a Burger King and suddenly you get 14 text messages with deals for Big Macs.
And here's a great scenario that is countered by evidence, given how the ability to track your phone location accurately already exists, as does advertising.
Imagine if the US Govt had the capability of tracking Snowden back in 2013.. or even today.
I don't need to imagine it. They were tracking him. He was an employee of the NSA. Their problem is they didn't act on anything until after it was too late. They knew exactly where he went and when and didn't think much of it until later.
That's the thing about tracking. People come up with all these wondeful doomsday scenarios that just simply don't pan out in pretty much every democratic nation in the world. Sure if I was living in North Korea the answer may be different, but then likely I would also have the common sense to simply decline the ability for a website to access whatever you think the latest privacy issue is.