John, thank you very much for the thoughtful response. I have seen indoor growing environments from that generation of greenhouses in both California and Iceland and have spoken at length with growers from The Netherlands. You are correct, there are pests in there.
However, the new generation of indoor growing such at Sprout in Kyoto and the modular, enclosed environments that are most recent do not have this problem. They are more akin to semiconductor clean rooms. Fully sealed, mostly automated, and the few employees wear clean suits.
These food factories, if you will, do not use pesticides. They do run the risk of a contamination or infestation (as a semiconductor plant would), but that is a risk to a crop loss and not a moment for pesticide application.