Bitcoin transactions take place between addresses, which are hashes of public keys. It's actually better to call bitcoin "pseudonymous", since the addresses are

Bitcoin transactions take place between addresses, which are hashes of public keys. It's actually better to call bitcoin "pseudonymous", since the addresses are pseudonyms that may or may not be tied to an irl identity. So if you, a hacker, tell someone to submit Bitcoin to an address, that address is only really "anonymous" until you use your private keys to reroute the money to other addresses. As soon as the graph of transactions touches some known node (perhaps at the edges of the Bitcoin network that interact with the monetary system), you can trace back to figure out who might have controlled the original address. It's very silly to try to cash in on ill-gotten bitcoin...