Unwanted garbage aka Kachra of society spreads only diseases, makes the ground and soil toxic , kills animals and humans alike. Pests however disturbing to humans, have a huge role to play in society. Without pests, like bees , the Earth will die.
Source : http://www.riverdeep.net/current/2002/03/030402t_insects.jhtml
Insects perform a vast number of important functions in our ecosystem. They aerate the soil, pollinate blossoms, and control insect and plant pests; they also decompose dead materials, thereby reintroducing nutrients into the soil. Burrowing bugs such as ants and beetles dig tunnels that provide channels for water, benefiting plants. Bees play a major role in pollinating fruit trees and flower blossoms. Gardeners love the big-eyed bug and praying mantis because they control the size of certain insect populations, such as aphids and caterpillars, which feed on new plant growth. Finally, all insects fertilize the soil with the nutrients from their droppings.
We see once again , without a doubt , anything is better than ‘Kachra’.