I threw soft snow balls at cars of friends, but never any rocks.
We use to get Cattle corn from a farmers field and on Mischief Night we would throw corn kernels at cars. We also would go up to town and soap windows. One time we soaped the widows of the Chief of Police’s car parked in front of a local pub. Just once a year though. Lol
Yes, rocks and even iceballs were a bit much. A friend once threw an “ice cream ball” at a car (he’d bought a small container and didn’t like it); the impact was so loud - he had no idea how much heavier ice cream is than snow...