Are you thinking about debit cards?
A debit card is issued by a bank and accesses a specific bank account at the bank.
I’ve not seen company issued cards directly accessing financial institution accounts.
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Or credit cards?
Store credit cards are simply a way of merchants getting people to buy store items easily – and sometimes at high rates of interest.
The card simply records purchases that are then files as “loans” in a credit register.
But … the flow of funds is all one way .. from the customers into the store in the way of checks or automatic payments.
Stores do not pay money into customers accounts.
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But either way it’s still a moot point.
A “card” whether it’s credit / debit or physical / virtual is only a number into some sort of accounting system … just like palyer accounts are already.
We still have the main problem with using them for player accounts :
(1) the US government is not letting US citizens deal with casinos – so players cannot pre-fund their accounts.
And it doesn’t solve the affiliate account …
(1) casinos won’t be able to allow affiliates to transfer this back into the US banking system.