I agree with this for games, but I think it's because you're actually controlling it instead of merely viewing it. It's satisfying to have more immediate feedback to your inputs. Watching a mouse cursor move at 24fps (say, in an instructional screen captured video) isn't as frustrating as operating a cursor at that rate. Feedback is always better when it's faster.
While the initiator is to blame for the situation each individual holds their own responsibility for how they respond.
Certainly not. If someone starst a fire in a theater, and a panic leads to a stampede, the only person responsible for anything that results is the arsonist - period.
Think of it this way, if a gunman entered a crowded room and shot some people, would it be acceptable to take him out with a grenade?
If he has body armor and is heavily armed, certainly. The context determines what the valid response should be.
I'd hate to see what would happen if a bunch of amateurs started firing in a crowded and smoky movie theater.
Whatever does happen, know that there is only one person to blame.
In short, would I want to spend every waking moment surrounded by people who are armed to the teeth for the highly unlikely offchance that I happen to be in a situation like this one at some point, and then hope that amateurs take him down without hitting even more innocent people in the smoke, darkness, and chaos?
You are discounting the effect that a society free of gun laws and fear of guns has on the decision-making of these sorts of people. Would he have bothered getting off his couch if he knew that many of the people in the theater were likely armed?
So no, you aren't arming yourself for an unlikely event, but helping make the event unlikely by arming yourself - in addition to promoting the easement of gun laws, and spreading gun education to reduce irrational fear of guns.
New York... when civilization falls apart, remember, we were way ahead of you. - David Letterman