zenga, Players feel that time invested in the game should be rewarded with increased power. Someone playing hours every day and raiding 7 days a week should be rewarded with better items than someone who logs in once a week. They consider this fair.

Note that "fair" means "the advantage I can make use of", and since most wow players would rather play more than to multibox they consider multiboxing to be unfair.

If you invest time and money into playing wow many people will already think of you as a hardcore gamer. If you have the hardware, software, dedication, time and number of wow-accounts to multibox then you are a hardcore gamer. You can use other terms if you like, but casual gamer would be very misleading.

MiRai, Sure, he probably has his reasons. It doesnt really matter if he personally likes multiboxing or if he is multiboxing himself, he has said its a problem in the game.

I think there are enough multiboxers around for many players to have formed an opinion about us, and players do notice multiboxers. Certainly seems to be a lot of activity on the official forums about boxing and there has also been several official (blue) posts about multiboxing.
It started out as a rare thing and now its becoming increasingly more common.