Isnt the range of Bluetooth pretty much the range of a loud yell?

Haha fair point. In open terrain you get maybe 50-100m which I agree, not far. In practice it's more useful than it sounds though. You don't need miles of range when the point is "where did my buddy go 5 minutes ago." And if they walk out of range their last position and heading stick on your map as a ghost marker so you're not totally blind or left guessing.