It was widely believed time back way back in the '60s that there was a place where it was the law that if two trains met at a railroad crossing, both had to stop and neither was allowed to restart until the other had passed.

In the real world and during that same time period we were once faced with a law which did not permit us to move from the bar to a booth or table carrying our own drinks. We had to get the barmaid* (as she was then known) to carry the drinks for us.

*If you think that's bad Ænigma wants to call her barn.