Think about all the Friend of Friend wire taps. Suddenly the $20 bill you bought starbucks with gets given as change to a drug dealer and you are on a known ass

Think about all the Friend of Friend wire taps. Suddenly the $20 bill you bought starbucks with gets given as change to a drug dealer and you are on a known associate list. While this is not something anyone who values privacy wants, this isn't that great of an example because the transaction history would show that the association is specious, as the association only exists through being a customer at the same establishment. A Venn Diagram of who "touched" which money wouldn't provide any value (this wouldn't stop people from making that association, I grant however). However, this sounds a lot like contaminated currency[0], and no one thinks that just because you have a dollar bill that has illicit drugs on it means that you're drug dealer or associate with drug dealers. This ends up working for the benefit of those in the illicit drug industry much more than it harms those who are not, despite that both parties are using the same medium of exchange. [0] http://en.wikipedia.org/wiki/Contaminated_currency http://en.wikipedia.org/wiki/Contaminated_currency