Not to mention, you'll have a whole catalog of conveniently inconspicuous profane words at your disposal. Next time your work PC crashes, just say 'Merde!'. :D
Conversely, the viewers should have the right to choose whether to watch a foreign movie dubbed or subtitled. As we have seen on this thread, that doesn't happen too often. In Spain, only the two major cities (Madrid and Barcelona) have a circuit of theatres usually showing subtitled films...
That assumes other languages use intonation to emphasize specific words within a sentence, which is rarely the case. For example, in some languages emphasis is achieved by altering the usual word order (placing the emphasized part at the beginning of the sentence), or using indicating words...
I worked in that field for some years, and it is a very complex job, which can be best described as "simultaneous written interpretation". If you are at all interested in the stringent conditions a subtitler works under, check here. It's by no means a definitive guide but you get the picture...
Spain is a "dubbing country" because of Franco's regime. It's much easier to censor an offending line on a dub than on an original-language subtitled movie (where a viewer with understanding of English would catch the trick). An example is the original dub of Casablanca, where all mention of...