Whether we choose to think about it or not, humans in their daily lives directly cause immense suffering to the little creatures. Leaving them half crushed, spraying poison, drowning. Have you ever observed these events closely, and possibly worsening the situation for the insect: tear off a leg, peel a wing?
When I was a kid someone told me you can take off a daddy long legs leg and it would still move so I tried it and it worked but then I felt really sad that it was missing a leg.