Spec-ops vs psy-ops, where do you draw the line?

My favourite role in this game is sneaking behind enemy lines and disrupting their logistics, whether by stealing materials and crates, or shooting or stealing trucks. The thrill of being self-sufficient, with everything you hold being risked in every engagement is great. But I find myself struggling a bit with the conflict between being effective, and being sporting and good mannered. The thing is, when you're working behind enemy lines, there are many responses the enemy can take to your actions, and the absolutely most effective for the war effort and your side winning is if their logistics players and scrappers simply stop playing (or stop playing that role). The most effective way to achieve this is to make that role unpleasant for them. But at what point are you just a griefer ruining the game for other players?

As an example, a typical interaction between me and one of the enemy's "safe" towns goes something like this: I run up to the scrap field, see a player slow-walking back to their truck, and pistol them to death before they can switch to a weapon or get to cover. Then I grab all their scrap and their pistol clips, and walk a screen or two away to drop the scrap. A minute or two later they return on foot, with a rifle or SMG, but I come out on top, and now have a better weapon. Then I check the players list and see that the player is no longer online. Did I just ruin someone's game? Did they quit because of me? I mean, this one is easy to justify, I can just tell myself that they quit because of the poor performance of their team in securing the line, in securing strategic spots like a scrap field, etc.

But what if they, while dying, complain? What if they're despairingly asking why I do this (explaining that it's a war game, and I am helping my team win is rarely fruitful)? Do I give them advice to keep their spirits up ("hey, get a squad to hunt me down" "you have tunnel network, just build a foxhole or two?" "scrap elsewhere for a while and warn your team, I can't move fast around your defenses")? I mean, taking action against me regardless helps my team since it takes resources and manpower away from the frontline.

Or do I actively seek to make their life miserable - taunt their and their team's efforts, perhaps sing a jolly song badly as I dance around them? Give them terrible advice?

I mean, I could go very far in driving the psychological warfare home here. I can't bring myself to do so, but I can easily see how other players might. Do you go all the way? Offensive language aside, there's very little in the code of conduct about dealing with enemy players. Are all things fair?