Edgewear in concrete
The photo above is edgewear in my driveway. The large wide gap is where a wood form piece was used. Normally, the wood form is a nominal 1×4. Where the concrete slabs meet the wood form the concrete will inevitably exhibit edge wear. The edgewear is ugly from an aesthetic perspective, but it is not an indicator of foundation distortion.
It does make the crack look much wider than it really is. As long as there is no vertical displacement, which would indicate a shear failure, there is aggregate interlock.