Like you, I wouldn't wish to take down a whole hive unnecessarily. We had European hornets, discovered when I got stung by a couple of them. I followed them from the back yard to their hive in a hollow trunk by our driveway. We left them go and watched them build the coolest nest in our tree! A month later, they started getting aggressive when our night lights went on and it was a mad scramble to get to safety when exiting the vehicles and entering our breezeway. Unfortunately, we had no choice but to eradicate them.