Some dings on the rear fender "could" be from the front wheels kicking a rock back. I had a detailer tell me this- I dunno if its true or not but supposedly cars with fenders that flair out experience this.

Anyone know if this is true??

 

Sen - No, this wouldn't cause it. That would cause a nick in the paint, not a rounded dent. I suppose it could happen if it kicked back a heavy racquetball though

Siepel- the Ding King is an "As Seen on TV" product...
http://www.dingkingtool.com/