What are professional methods for preventing pantry moths? For about a month I have been fighting with a pantry moth infestation and that got me thinking... Professional businesses (bakeries, restaurants, factories that produce milkbars or cornflakes) take in much more food than I ever will. Therefore the probability of them buying an infested product (like pantry moth-infested flour) is much higher than in case of my home kitchen. And the costs of production halting or throwing away infested food is much higher than in my case. 

What precautions are taken by professional businesses to minimize the risk of pantry moth infestation? Can some of them be implemented in home kitchen?
Honestly, the top reason is going through stock quickly.
My apprenticeship bakery took delivery 1X week for most grains. Milled daily.

The second strategy was tightly sealed plastic tubs.

Third, deal with infestation in early stages. isolate and destroy.
It was an organic bakery so, yes, occasional uninvited nibblers.