That's really funny, and probably quite true. A lot of the UK forget the Queen has a 3rd son, let alone a 4th child. They all know Charles, Andy and Anne but if you say "Prince Edward" they respond with, "Who is that?" Then if you say, "The Queen's possibly gay son," they respond with an enthusiastic nod and "Ohhh yeaaaaaahhhhh." Gotta admit, Sophie was brave taking Edward on, even though we know he isn't actually gay, because no doubt she got a lot of stick back in the day. (Particularly her, "My Edward's not Gay" headline. She also fervently reported before their marriage that "Edward is DEFINITELY not gay, I can tell you that." :O living in sin, the outrage of it all!)
I think Edward and Sophie prefer it that way though, as they do not really like to be in the limelight that much. I am sure the Islanders are aware of who Edward and Sophie are though as they have both visited the Carribbean a few times before. No doubt all the countries wanted "Wills and Kate" but they can't go everywhere!