Hello,
for my type of game, it is very difficult to play as a guest: a game lasts several days, you play with 16 other players, with which you exchange messages on the forum of your current game. For these reasons, you have to be clearly identified to the other players. The mail address is not verified if you don't try to abuse the game, it is only used to login, and to recover your password if you lost it.
By the way, the game is only in french.