I worked in the photo business for a chassidishe fellow 30 years ago, and
I can tell you that such geneiva was widespread. We were pressured to sell the batteries and cases (that came with the camera) separately.
After a cash sale, the owner would joke that the tax was “gravy” (because he had
no intention of reporting it).
So for those of you that think this doesn’t occur by yidden,
you are sadly mistaken.