Is there any point in collecting puzzle pieces in Donkey Kong Country Returns?
Solution 1:
No there is not. The extra gallery items are the only reward.
Solution 2:
The bonus levels are for rare orb balls. If you have all of them you can open the door of the golden temple.
You get the golden temple if you kill the endboss.
You get the bonus level if you have all of the kong letters in every world.