There is some negative camber designed in to provide better tire patch
on hard cornering, and usually the negative camber increases as the
wheel moves up to compensate for body roll. On the W124 it's visible
but not dramatic when the suspension is in good shape. When the spring
link bushings go, and/or the camber link rubber, it's very obvious,
ditto when accompanied by sagging springs or missing spring seat rubber.
Obvious negative camber means something needs to be fixed, usually.
Tire wear is also a bit higher on the inside, but at normal condtions,
the tread sits pretty flat on the road because the radial sidwalls are
fairly soft. BMWs have more negative camber than Benz, for instance,
but I've never seen that much more tire wear in the back. Rotating
tires correctly will also even things out.
Peter