It's the primary reason why running an exit node on your own is considered an unwise move. That guy is responsible for the IP addresses he uses. A telecom company, on the other hand, wouldn't be.

https://www.torproject.org/eff/tor-legal-faq.html.en

I don't see how that answers my question. A non-zero risk does not mean "In all likelihood" things would unfold as you have depicted them.