Welcome to OCDO!
Sorry about the unfortunate experience with a moron. It happens from time to time. You did a good job though, with keeping your cool and acting responsibly. With people that are looking for a confrontation of any kind you will find that they will only get angrier when their efforts are ignored. Just smile and say have a nice day... or as you did just ignore it altogether (but remain alert) if diffusing the situation with a simple "please calm down" or the like didn't work.
Have you been in Lynchburg your whole life?
Edit: Which Sheetz was it?