Unless there's a player flying across the sideline at the bench to get a loose ball who totally wipes out the chairs, as a coach, I don't really see why you would have any reason to pick up a chair at all during the game, unless you were about to use it as a prop to make a scene. First, in order to pick it up to do as your situation suggests, you'd have to go around behind it, which is pretty dumb to leave the bench in the first place. Second, slamming a chair seems like something that you'd have to think about doing...doesn't really fit my definition of a "spontaneous" thing to do. If I did what you suggest, I'd not be surprised to get T'd.
As for your second situation, are you talking about being seated and stomping the floor with your foot? Or actually standing there and stomping the seat of the chair? In the former, I'd be very surprised to get a T for reacting to my players without some sort of accompanying language. In the latter, regardless of why it happened, I'd expect to get T'd, and get a reprimand from my admin if at home, and a bill from the school if on the road!
