The blame should be put squarely on the shoulders of tophatter.com. They know the quality of what is being sold and choose to look the other way for the sake of making commission and sales fees on these imitation goods. In my estimation and also the interpretation of the law this is outright FRAUD.
Inverse operations are opposite operations that undo each other. Addition and subtraction are inverse operations. Multiplication and division are inverse operations.
Inverse somewhat means the opposite. The inverse of addition is the opposite of addition which is subtraction (the opposite of adding 5 is subtracting 5). Subtraction undoes addition and vice versa. So they are inverse operations of each other. Another basic pair of inverse operations are multiplication and division.