In the past, as a subscriber, if the New card was one you already had, they gave you a credit of a ticket to your account.
I think the new system makes sure that you always get a new card.
Once you have all of the Cards, you won't get one every day, just the new releases.
Many members stop their subscription after gaining the Full card collection and then purchase tickets to buy the new releases.
Just starting out, the subscriptions are the most cost effective way to build up your collection.