Placing the blame on American players only is bias and untrue.

Even saying "majority" still implies "more than average" which is also very untrue.

Its a mixture of people who do it. You only see one type because that one type are generally online when you are online. I'm very sure that Chinese, Australian, French, British, and Latin American players have also "stole" mobs from other players. Placing the blame on the "majority" of American implies that all American players are bad players.