Putting your life at risk whilst deadheading
This indeed happened a few times. Once out of SYD whilst deadheading, as the plane turned into runway 16R I spied an aircraft on tow crawling ever slowly about to cross ( west to east ) the edge of the runway. As the plane was aligned with the runway, I lost sight of it. I thought it was just a line up and wait instruction. However the crew did an immediate rolling takeoff ( they indeed had tower clearance to takeoff ); I told myself that the aircraft on tow must have held position very close to the runway. There was a more abrupt rotation than usual and I knew that something was wrong and I did not see any towing aircraft throughout the takeoff.
Later, when things settled on cruise and the F/O came back for his rest, I confronted him about the incident. He related that they were filing an airmiss report as the Tower had cleared them for takeoff and the towing aircraft was at fault. Fine....i then ask him if he had seen the towing aircraft close to the runway edge prior to takeoff, he said he did but didn't think it would encroach the active runway. I asked if he and the skipper had any doubts and reconfirmed with Tower to which he replied it didn't cross their minds that the towing aircraft would encroach as they already had takeoff clearance!!! Alas, doing things blindly and by rote is the Korean way!!