We were told by the CO at a pioneer meeting that watching R rated movies would mean immediate removal of privileges. Most folks simply did it in the privacy of their home or drove to a theatre out in the middle of nowhere. There was typically some excuse as to why it was okay to watch certain R rated movies. As far as I know, R rated movies are still a big no-no.
Many R rated movies in the US carry a comparable rating of G in other countries.
I remember while living in another country and seeing a movie that was rated G there but R in the US. When I talked to folks back in the US and said how great the movie was they told me I knew better than to see a R rated movie. When I told them it was G where I was, most informed me that it didn't matter and if its R in the US, thats what mattered. However, others used it as an excuse to go see the movie.