Kelemelan is indeed correct. The “free pack” is just a counter on your Profile you can exchange to any of our current or future packs. There are a few in our Special section which can’t be bought but can be acquired by using the “free pack” system by completing achievements and inviting new users for example. If you don’t need them you can just save your “free packs” and when we release a new pack next you can get it for free.