It is regulated. Every transaction you make at MtGox into a government currency is being tracked and recorded. Why do you think they have withdraw limits? They are a money changing business. The US government could seize their funds in a heartbeat. What good are your bitcoins if you can't easily trade them for cash.
They'd only do that for specific reasons, for example to stop tax evading.
Go smoke some more weed
Go smoke some more dollars
