If I understand you correctly - that people are swooping in and killing your targets - it's relatable. On Europa, I'd say at least half the regular Invasion participants are entirely scripted. They all move around the same way, they all engage enemies the same way, and they basically never pause. I presume they are at their computers watching the script execute though, to respond to edge case scenarios.
A few hours ago, the Invasion on Europa was at Moonglow. I died at one point and ran out the town for a wandering healer. Shortly after resurrecting, two players running scripts somehow ended up outside the city fence, and were therefore sweeping through the forest killing ALL the animals they encountered, in the exact same way they do for the invasion mobs.
It actually doesn't irritate me that they are scripting, but they do sometimes drag paragons around with them, even dragging them over to the Artifact Turn-In/Healer NPC west of East Britain invasions, which has resulted in me getting res-killed on one occasion. That's the real irritation: they sometimes drag spawn around and cause problems for others, I find that more annoying than them killing a mob I'm in the process of one-shotting with a flamestrike.