Really? Is that what you believe? I guess you are saying this because when you hear gambling, it is probably termed as a bad thing or bad people because they gamble. Good gambler does exist and apart from the ones OP mentioned, they are gamblers whom believe in fair game and in fair wining. Some gamblers are good at manipulating the game to their own farvours and become greedy, these are the people you might want to term as bad gamblers.