Yes, multiple (trans)actions in one session are a use case where it would make sense to keep the card until the end. I'd say it would still make sense to return

Yes, multiple (trans)actions in one session are a use case where it would make sense to keep the card until the end. I'd say it would still make sense to return the card before the cash and have the user insert it again - a small inconvenience for the few users that want to do multiple actions but probably a big decline in forgotten cards.