Quite odd find by Stickination :>
At the end of the game where it shows the final score and then does "+500" (indicating your match bonus).. repeatedly tap Square and Circle very fast.
Step 1: Finish the game.
Step 2: Wait for your Match Bonus to flash on your screen.
Step 3: Tap Square and Circle fast when you see it.
Step 4: Observe your Match Bonus go from 600 to 1800-2000.
Enjoy I'll throw some proof up shortly.