I've worked for peopel who have avoided sales tax before. It's actually quite easy from what I can tell.
This is espiecally easy if you get your products overseas as you can always just pay for a certain number of products on the record at an inflated cost and have them ship more to you. These additional items just never being recorded in the sales logs with the extra profits pocketed.
Having one point of sales just makes it easier because they can do it on a smaller level and reap the same amount of profits if not more.
Other commonly done practices include marking some units as either stolen, damaged during shipping or replaced with defects. Considering the large number of products that can be destroyed in some places this can be quite effective.
For example, some distributors mark products as damaged, that were, the cans dented, boxes slightly ripped. (this hapens A LOT) and then turn around and sell these products to the workers at the plant/store to stores for cheaper goods or just to other people they know. (Or just pocketed themselves.)
There would be a much greater reason to "accidentally" rip the packaging on these items, or even just mark them as such like above.
The way this stuff is done, a looking over of the books or a manifesto isn't going to work, and even hands on inspections are pretty impossible to nail someone on.
