According to this, one of the attendees of the concert threw the bottle at a passing car?
Did they initiate this action in a "non-violent" way?
Of course, I do think that the reaction of the people in the car was over the top, and that they should be arrested, charged, and tried.
But, that aside, to be morbid... "Someone brought a Peace Activist to a gun fight..."
in Kalifornia, the driver would have used the car to mow down the bottle tosser.