A lot of new cars have the rear wheels cambered in as stock to counter a tendency to oversteer.

New cars, see, have much stiffer bodies and suspensions than old cars. A stiffer body means keener handling. Unfortunately, too stiff a body and suspension and a car will have the tendency to snap-oversteer under sudden braking in turns, because the rear wheels lose contact with the road.

This is great for racecar drivers and boyracers, but for 99% of drivers out there, it's downright scary.

To counter this, manufacturers are putting negative camber on the rear wheels of cars with a stiff chassis, like the Mazda3. On other new cars, like the Honda City, the beam axle in the rear doesn't give you adjustable camber, so they resort to other methods, like using thinner anti-roll bars and sway bars to "soften" the rear suspension laterally without losing vertical stiffness.