If they are US based they really need to change their view because it is money laundering, a court in the silk road cased said it is and that could easily be used in a suit. I say KLEE brings a lawsuit up against Bitmixer.io (he now has enough funds to cover the initial cost) and i am sure they would give the information over soon enough.
This money laundering has both merits and demerits. We can't tell them to close laundering but they can make it more better especially when someone ask laundering a great amount of BTC. It is really bad that this service utilizing in a worst way.
Kindly,
MZ