> As far as I understand it, it's very hard to track that kind of obfuscation
You understand it incorrectly, then. Bitcoin is not anonymous and transaction flows through the network are very easy to trace. Additionally, it is very easy to link specific transactions to regions or even specific network addresses/services.
Yes, it's not inherently anonymous. But it is possible to obscure the owner of the coins. It's not foolproof, but it probably makes it a little harder to figure out who is doing what...
You understand it incorrectly, then. Bitcoin is not anonymous and transaction flows through the network are very easy to trace. Additionally, it is very easy to link specific transactions to regions or even specific network addresses/services.