If they are common or annoying insects I usually don't mind killing them. I personally never kill spiders because I think they're cool. Funny that you make this thread and mention bugs. There was an annoying cricket where I work -driving me insane for a good week. When I took out the garbage a week later (a couple days ago) there the cricket was, under the trash can in the corner of the store... I never felt so much joy killing an insect.
I've also killed a fair share of lab mice. It was shitty at first but then you get used to it. It was for science after all.
I am the black sheep "of course I'm crazy, but that doesn't mean I'm wrong."-Robert Anton Wilson