<< Why would you get involved if the sniped party doesn't report? And why doesn't the fact that the sniped party didn't report constitute proof that he was consenting to be attacked, provided that he's otherwise obviously active and aware?

Some players (especially newer ones, who are already among the more likely people to be victimized unduly) don't know about the REPORT command. The fact that someone doesn't REPORT doesn't necessarily mean they consent to whatever actions are being used against them. :)

It's safest for everyone if we stick with an "active" consent scenario rather than a "passive" one, therefore.

Maelona