I highly doubt anyone here does this but:
It isn’t hard to imagine that somewhere, “someone” wanted a way to bring millions of people into a program where they could be tracked, have their phone mined for data, and have who knows what other ‘third party’ stuff slipped into their phone. Disguise it as a game and people will line up to hand over their digital keys.
Or, perhaps it’s just a game.
But, to me, it’s just an unnecessary risk. If someone were to really want to play this game, I’d suggest buying a burner phone and using it instead. Expensive as hell, but you probably shouldnt be wasting your time playing this modified and rebranded version of geocaching anyway.