You've already had the best advice. I would only add:
A "new" trick only works the first few times against an adversary. Countermeasures are soon developed and implemented.
Now that you've had time to think about their trick, you should form a plan of action, and be ready to implement it the next time this occurs.
A vet told me once that when someone is continuously shooting, he is so busy looking straight ahead, that he can be snuck up on and flanked. I suggest flanking, whether with gun or video-camera.
Were it me, and if I was *sure* that I was being "terrorized" by a-huggers, I would look for the opportunity to sneak up on them, and shotgun their ghettoblaster. Alternatively, you could seize it, carry it to your truck, and run it over several times on the way out.
---------
"No prisoners"