Your arguments are still dumb. (Sorry, was trying to use a nicer word)
Would you rather:
(A) Be in a crowded theater with a gunman shooting everyone.
(B) Be in a crowded theater with a gunman shooting everyone and an armed civilian firing back to try and save lives?
All of these gunman have a plan in their minds. When their plans are interupted, they panic and flee. They're cowards. No different than a bully getting knocked in the nose by some kid they're picking. They done rather quickly.