So when you play characters that have incentives to kill it is up to you to toggle it. Sheesh it should not be that much of a problem unless you are a newb in which case you are fodder anyway. Have the default toggle set to on. Nofollow, autoloot, etc are all toggled so why not this?

As a function of RP like some mentioned imagine being an AP standing over someone near death and mocking them, simply a blast without having to multi-kill that damn loser who is giving you NO charges anyway.

Cheers,
Arzzra.