few things observed:
1. not knowing the rules is not a defense to the violation of the rules. Public policy dictates that, unless we all prefer chaos; as between rules and no rules, order and chaos, there is no middle ground.
2. Participation in a referral program as a consumer on a sporadic basis hardly qualifies one to be MoT.
No one should raise any controversy that MoT also means Member of the Commerce; with the subject of the commerce being the audio product. No one should further raise any controversy regarding the nature of the commerce; which in this case most of the commerce is interstate, as in the product has traveled through several states, or between the several states and a foreign state.
We can therefore re characterize Member of Trade as Member of Interstate Commerce of which the audio product is the subject.
So the question is what type of activity would qualify someone to be engaged in interstate commerce. At one end of the extreme you have brother A selling his headphone to brother B in another state and B gives A consideration in exchange for the headphone. At the other end of the extreme, you have AKG shipping and selling millions of headphones across multiple state lines throughout the country to millions of individual and businesses.
It is without a doubt that AKG is conducting interstate commerce while the brothers are not, to say otherwise is to twist the word 'commerce' beyond what's reasonable.
To distill the former example to a general principle is to say interstate commerce does not mean singular or isolated selling of goods across the states, rather interstate commerce requires a systematic and multiple selling of goods across the states, or at least a desire to systematically sell multiple products across the states.
The recipients of most friends referral program benefits can hardly be characterized as interstate commerce. Granted, if the recipient receives systematic and multiple benefits from program benefit offeror, it is certainly possible to say that he recipient has engaged in interstate commerce; since there must be a direct and proportional relationship between the number of individual commerce moments and the frequency of those moments.
Therefore if the offeree of the referral program has only received benefits once last month, the person cannot be characterized as Member of the Interstate Commerce on audio products; on the contrary, if the offeree of the referral program has been receiving multiple benefits from the benefit offeror and there is direct and proportional relationship between the number benefit giving moments and the frequency of those moments, then it would be a good policy to label the person as MoT.