Lateral deflection of the leaf spring's main leaves combined with compliance in the spring bushings can be significant. I can't even dive the Valiant into a corner very hard yet and I can use up the ~3/8" of clearance between the inner fender and the tire's sidewall. Some form of lateral location has been considered just to stop the rubbing as I can't 'bump' the inner fenders any further out of the way.
Late model Mopar SUV's have a Watts Link under the rear, I've watched a few going down the road.