Is there any way to link the games/play account/icloud accounts to a wallet with limited funds? I feel like the real problem here is how these games link up to

Is there any way to link the games/play account/icloud accounts to a wallet with limited funds? I feel like the real problem here is how these games link up to a payment method that isn't actually intended to be used for the game. Unlinking them from each other should go a long way to resolve these "my child spent a lot of money because I gave them access to all my money" problems.