As far as I know, casinos usually deduct it directly from your remaining balance. If the balance is not enough, they may send you a notification requesting to add more money to your account. If you skip adding more money, your account will be permanently canceled or they may deduct your money when you deposit money back into that account again.
If your account is linked to payment methods such as credit cards or cryptocurrency wallets, they can deduct fees from there even if your casino account has no money left.
We have people that are willing to engaged in the system and making huge profits. There's no option left other than persuading for crucial planning and a fruitful existence for ourselves in the system. The system is broad enough to absorb the necessary and unnecessary events in the system. We should always be at alert and know the next moves of your opponents. Inactive accounts will be flush from the system, we just have to be careful inother not touch the terms and conditions.