All I can say is that English differs everywhere you go in the world. Some people like to spell colour like that rather than color. As far as "the government are/is...I would say "the government is" because it is similar to saying "my family is." You would never say, "my family are." Watch out for those Latin words that sneak up though, such as data. "The data are" but "the datum is."
I would say the drug trade, too. However, it is such a subtle difference, I wouldn't worry too much if you see it written another way. It is sort of like "toward" and "towards" in that sense.
- For Teachers