[bdcravens]

They're likely moving the Bitcoins to their own cryptowallet. At that point they could spend on sources that accept Bitcoin for payment (Silk Road and the like, Reddit Gold, the small but growing set of real-world places that take Bitcoin, etc) or could transfer to an exchange to cash out.

tl;dr - both.

[hvidgaard]

Problem is that the coins can be traced, so they need to spend them anonymously.

[hackerboos]

Couldn't they tumble the coins and cash out?

[Xdes]

Tumbling simply makes the accounting harder, but not impossible.

[hvidgaard]

Even if they do, the mixing service must be anonymous too. The blockchain provides irrefutable evidence, and you need at least one step to make the coins anonymous.