We must able to share extra Chocolate Frog Card to another so that our extra Card can be useful to another person.
I don't think this is going to happen, because there is the feature to exchange doubles for other cards.
Like i was trying to say that, I have 4 Harry Potter Wizard Card and i want to give 3 of them to another person.
And like I said, I don't think it will be implemented due to the other functionality
Customer support service by UserEcho