It would in the same sense as illegally attaching a wire to the power cables and drawing electricity out of them does. You're stealing a limited resource (in th

It would in the same sense as illegally attaching a wire to the power cables and drawing electricity out of them does. You're stealing a limited resource (in this case radio bandwidth in an region for which you haven't purchased it, in the analogy power), but you're not doing so any more than a legitimate user would be assuming it's done "properly". If too many people do this, things stop working, because you exhaust the limited resource.