from what I have heard (not sure if it is true) you will be able to delegate your cards out. Just like you can delegate steem power out. Like passive income. You just gather all the cards then you can rent them out to people.
Example: I want to play in a gold foil tournament but obviously I can not afford to buy them. So I jsut rent them from people and they delegate them into my card deck so I can go beat up on the whales that own the cards.

Once again this is just what I am hearing and is not set in stone yet.