Cheating is when an action performed by a person is illegal and can be proved, or is obvious. Counting cards can't be proved EVER, since it's in the persons head and is just chance and statistics. Using a maphack can be proved as the software can be located on the cheaters PC.
But casino's, gameservers are property from a peron/firm. They can set the rules as they wish and interpret them as they wish. If a casino decides to remove a player, they can for any reason. In fact I believe every gambler should be pointed on that fact.
Online games cheating? if the admin decides he's cheating, then the admin can do what he wants as it's his server, if Blizzard decides any external programs or bug exploits used to cheat is cheating, it's their right to deny you to play the game, on their servers. (battlenet)
