Yes the tires do chase the grooves in the road, but that wont provide the sensation of wiggle room. In that situation, the car will just go and the wheel along with it. If I were you, I would just go get the alignment checked on the front and rear, along with the tire balance and inflation pressure. Maybe something needs to be tightened up with the steering. My crossfire has never had any wiggle room, it is tight and precise and its been that way for 62k miles. Good luck, its not a big issue and I'm sure you'll have no problem determining the cause of this minor imperfection to such an amazing vehicle.