when we had extra freezers we kept all of our "working" supplies in there, and then bring out some as we need it.
since down to only one freezer, have had to put the 25- 50lb bags on a dedicated shelf, bring them out and pack into buckets to make room for the next freeze treatment.

I go through a lot of flour & grains, and have never had any bugs show up after a first freezing.

the worst culprit for pantry moths seemed to be foods bought in cardboard boxes from chinamart..
it happened so frequently it started making me wonder if they were doing it on purpose.