Hello busamad,
Thank you for contacting us. I'm afraid there is nothing sinister going on here, it is simply as the name suggests: These are 'guest' players.
There are certain advertizing links, they've been around about 2 years, that allow a player to "try" tribal wars (as a guest) without the need to register an account name and email. If the player likes the game, he can choose a unique name and register the account. Otherwise, the 'guest village' will disappear after a while.
I hope this helps.
Sincerely, Seagryfn
Senior In-game Moderator
That's the answer shame about that should at least let them barb out.