About 30 cockroach species out of 4,600 are associated with human habitats.
Not gonna erase what has a good function in nature. That is the majority here.
Thinking about a whole bunch of insects, but all on a individual basis.
Will take time to prepare that.

Someone told me he still had fruit flies:
Killing a virus...scambling the DNA.
Killing a bacteria...sometimes scrambling their DNA, other times just stop the multiplying.
Ending a more complex being, like an insect...preventing reproduction. Sometimes also killing their eggs.

There is another reason to be very diligent in acting against insects. Insectoids are the most successful beings currently in the universe. Dont want to piss them all off because of stupidity. Some of them are great beings.

Some others complained they had mold on bread.
First...by bread more and trow the old away in time.
If you want to keep it longer, save it in the fridge and only take out the slices you need.
Mould on bread is not necessary dangerous to humans.
And I like blue mould cheese.

You see, this stuff might be more complex than you thought.