My ex wife once got frustrated at a blackjack table and went "all in" betting almost $2,000 on a hand. She got blackjack, collected her winnings, and went to play slots and wait on her friends.
Security came to get her. Turned out the table she was at had a $1,000 limit, and the dealer should not have allowed her to bet the extra $900 or so. They wanted her to return about $1350 of her winnings, or else leave the casino and be banned from Harrah's everywhere.
She took the banishment, which was good for her, but then I was tasked with trying to appeal it. It wasnt going to end well.
As for card counters, as long as they arent coordinating with other people, then they aren't doing anything wrong...but the casinos can refuse service to anyone they want. They dont have to allow a card counter to just take their money. Most other games, it doesnt matter how good you are, if you keep playing you will lose.