In that case they weren't protesters, they were a mob. They had just broken out store front windows and set a couple fires. The QRF, Quick Reaction Force, responded and those two police cars were the first ones to arrive. If you notice it was more of a push with the car, then a drive through. Should they of waited for more officers, we don't know the whole situation. They're just trying to do a difficult job, in a very difficult situation.