250 credits for a pack of 10 JOKER cards
That's a lot to cheap. Maybe 250 credits for ONE Joker card.
They make more money with the crap gambling games and screwing Premium members with full collections.
In total, yes ... but not per member.
Currently, I get cards for around 11 credits thanks to my discounts (Triple Diamond and PREMIUM). Paying 25 credits per JOKER would be more than TWICE the usual price.
But, if you insist - then price the JOKER cards at 50 CREDITS each, make them only available to PREMIUM members and discount them to the member level.