I think man is to a point where they can understand what each other are saying without correcting them, Niliscro. The conclusion I have over this matter is simple; The diplomats, having come from a different country, can have personal taxes dropped upon doing official duty. This is absolutely legal, and from this perspective, realistic. The Ambassador goes the same way, having come from another country in this situation. So I can see perfectly well now what you're trying to portray in these jobs special perks. But I do have one question, will these jobs ever have specific functions?
Also, scrub out the "don't take this personally" message, because I forgot how you've grown up as well as I have :/