That's PRECISELY the point! We already know that the my truck's forward movement through its tires is negated by the ground's backward movement, so the net is ZERO. The only way for my truck to move FORWARD (in spite of whatever the ground is doing) is to be provided a means of forward propulsion that is not related to the tires or to the ground.

In your treadmill example, you're basically saying that if I place my treadmill on the shoulder of the freeway, and I stick a winch cable to my bike then toss it out so it catches a passing truck, I'd be able to stop that truck dead in its tracks because the treadmill would prevent my bike from leaving the treadmill. That's absurd! I'm not GLUED or BOLTED to the treadmill surface, I'm just traveling on top of it!