I often have drunk idiots yell at me from passing cars while walking with my dog. I guess there are people out there whose only idea of fun is to get drunk, get into the car and yell and scream or throw stuff at anything that moves. Or doesn't - everything moves from their perspective, even lamp posts, after all.
I think you're lucky they haven't shot at you - I have seen road signs riddled with bullet holes. Somebody either aimed at a road-side photographer and missed or they aimed at the sign and hit it...
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