Count yourself lucky for wherever location you are at.

Here the CVS POS is set such a way that it cannot do split payment with debit mode. Period. A cashier even turned the screen to show me, even after she tried to put in the amount. Let alone autodrain.
Many people in some parts of the nation also have the same issue using debit.

Credit mode seems no issue but then it brings up another issue that if your CVS insists the "credit card" must have your name on it that matches the driver license. That is exactly the case in 90% of the stores here.

Here there are stores allow multiple cards to purchase but only that they must be on single transaction with SINGLE payment card. So that immediately preclude the split payment mechanism. Then there are stores allow purchase of 2 cards in separate transactions, but some POS would flag a false daily limit if the same register is used to do b2b2b transactions even with different IDs, though it is not the case for some other POS, even just a few miles apart.

Bottom line - each person must learn the situation of his own location and adapt what works what not accordingly.

Hence, saying one has no issue on doing this or that, without a warning of "in my area", is quite misleading to those who are new or uninitiated in this game. Just a friendly reminder.