Part of the reason pesticides are widely used in agriculture comes down to the general preferences of the average American consumer. Farmer Don, a local Portland farmer who grows and sells a variety of fresh foods explains the fussiness some people exhibit toward fruits and vegetables—they won’t buy if something is blemished or has any insect holes. As he tries to explain, imperfection is a part of nature, and an insect boring into (say) an apple causes only a cosmetic harm. Using less pesticides reduces the risks of contamination to the surrounding environment, and also less exposure to farm workers, and ultimately to eaters.
Check out this related video about farmer Don: Sunflower Seeds Forever