"Is it possible in reality? How is it implemented in practice? Thank you in advance! "
Yes it happens all the time. There are many posts in the forum complaining that they haven't got the refund yet but Turbo Tax took the fees out of their bank account. Turbo Tax debits your bank account.
If you don't pay they will automatically debit your bank account. You had to agree to it. Then when the IRS does send your refund they won't take the fees out again. Here's a FAQ on why you got charged,
https://ttlc.intuit.com/community/charges-and-fees/help/why-was-my-bank-account-auto-debited-for-tur...
