Air Via is doing charter and ACMI business (mainly the latter in winter season). Do you think their pilots are examining all such details behind each of their "mission" carefully before going ahead and fly?
They simply go and fly whenever they needed for firefighting as that's how their company makes living (and they do it bloody well if I can add). It does not mean they agree/disagree with the purpose and reason of your action (which by the way they hardly knew of), they are just doing their job.