1. More diverse strategies longer playing value for customer
2. Harder to get that one card you want bad more likely to buy
3. More counter strategies forces pay players to put more cards at level 20-30 to maintain diverse counter strategy rather than just making 3 or 4 cards level 50. This balances game for unpaid players. If pay player put all rubies into one card just make sure there are good counter strategies against that one card.
4. Easier to give cards away as reward as there are many many more out there ready to be collected. Incentive for new players
5. And last but not least so we can see new artwork.
