since I drive alone most of the time, the weight bias on my car is on the left. So when I place the sandbags/gravel bags in the trunk, I offset it a little to the right, to make the left-right weight distribution more equitable.

otherwise, when I hit the gas in low-traction conditions (which makes the rears spin and lose lateral grip as well), the car will want to rotate counter-clockwise (viewed from the top), around the center of mass, which is a bit on the left side due to my mass.

with more weight on the back, I now have to adjust my Euro headlamps so as not to blind oncoming drivers (I wish I had the vacuum headlamp adjuster).