I'll point to Blizzard's Hearthstone (still in open beta) as a counterexample. It's a collectible card game, and it's perfectly fun to play from day one with little more than the starter cards. You can earn more cards slowly by playing a lot, or you can just buy them. But while buying better cards can make you more competitive, it doesn't necessarily make the game more fun, since in any case it generally matches you up against an equally-matched opponent.