There are two errors in the first sentence of this article. Two of the 4 chemicals are NOT used on crops, but are placed in the hives by beekeepers to control mites that parasitize the bees. Mites are NOT insects, they are arachnids (related to ticks).
You are right. But not all beekeepers use these harsh chemicals to control mites. Husband and I are hobbyist beekeepers and we avoid using these for mite control. Of course, we lose a lot of bees each year, but are willing to do that in order to have honey that is chemical free.
Thanks for catching that.