In any case, it's not just about what you can and can't do, but how easy it is to do it. If I want to send $10k to someone on the other side of the world to fund a terrorist operation, it's a heck of a lot easier to buy a few bitcoins and send those than it is to physically transport that much cash. And just because we can trace bitcoins, that doesn't mean that it's easy to do, or that someone really watches for "suspicious" transactions. If a $30k wire transfer is initiated, someone will probably pay attention to it. If someone sends 50 bitcoins, no one will pay attention or care.
You don't even have to send 50 coins.
All you have to do is share a private key.