Luck is the only answer in gambling regardless of the amount of money that the player holds. If there's a method to make a profit out of 0.01BTC, then people will just use that very same method but with higher base bet. For example, a method that works for 0.01BTC will be used by a user that has 0.05BTC but will just multiply the bet by 5. There's no good strategy at all in gambling. All of those people in the leaderboards just got lucky back then.