> Note that card counting is a "loophole" to this idea, since nothing about the rules of blackjack prevents you from memorizing cards, and thus it is not against the rules of the game.

Typically in these cases the house is limited to either ejecting someone they decide is a 'counter' after they win the hand, or applying countermeasures such as having two decks and shuffling one while the other is in play for a hand (and then using the shuffled one for the next hand.)