Hub-Centric:
A hub and wheel design in which the wheel is centered on a raised center portion of the hub. The lug nuts/bolts then serve only to hold the wheel in place on the hub. Most tire balancing machines use a conical wheel mounting mechanism to locate the wheel/tire on the machine for balancing.
Lug-Centric:
A hub and wheel design in which the wheel is centered by the lug nuts/bolts themselves, often with clearance between the center of the hub and the cut out in the wheel. Toyota wheels are lug-centric and as such require a special lug-centric fixture to be properly balanced on a cone-type balancing machine, as the wheel center hole may not be exactly centered on the lug center point.
4Runner wheels are lug centric. That's the whole reason for the Haweka adapter, to center the wheels on the machine. If they were hub centric you wouldn't need it, hence Jaos wheels. You don't need to use the Haweka if your own Jaos wheels, since they are centered at the hub.
4Runners in general have a very sensitive front end, and it anything is off just the slightest bit, you will feel it. Not every lug centric wheel needs the Haweka, but you will on the 4Runner is you want the best balance with your stock wheels.
Jaos brand wheels are hub centric, thus cost MUCH more $, and you won't need the Haweka.