Here's a thing to think about:
If you want to try and do your bit for the world and live a bit more aware of the ecological impact you have on the world, how far should you take it:
Do you let slugs live in your garden to eat all your food?
Do you kill mosquitoes that suck your blood?
Do you let nits live in your hair, because if they make their home in it, that's where they want to live?
Do you take a milder stance and try to rehome them:
Collect and leave your slugs elsewhere so they annoy someone else?
Try and catch mosquitoes to put them outside? (good luck!)
Removing your lice/nits and find a different home for them?
Or do you just say fuck it and poison them all?