I've had this happen to me at the gas station before and at a red light.  I always am by myself too....but normally if someone says something to me, I just turn the radio up even more turn look at them and flash a huge smile and go about my business.  I normally don't have techno playing....but rap...every old person's FAVORITE music!!! 
 
I think I hate walking near them then driving near them more though.  They walk slower than they drive!