I do not remember anyone saying that reason to leave is "lack of knowledge or lack of resources". But I heard from many people that they have nothing else to do, they was asking for account reset so they can collect all card again. I go only from your number 66000 boosters. I take into account a pesimistic estimation 5000 players. And count 3 starting boosters, few boosters for achievements for completing first few maps, then achievement for completing daily quests, then achievements for co