So yeah it's an idea from the Monster Hunter team.
Famitsu interviewed Monster Hunter series supervisor Ryozo Tsujimoto about MHP3G and the slide pad expansion. The device provides a good grip on the system, said Tsujimoto. He jokingly referred to the expansion as a "secret weapon" which will allow you to play the game with the same feeling as playing Monster Hunter 3 on Wii
Ok guys the CC Pro was neat, this one not so much.
Well the article also say this: "It's unclear if Nintendo made the device specifically for Monster Hunter 3G, but the device is introduced in Famitsu's reveal article on the new 3DS Monster Hunter game."
I hope this is not mandatory to play MH or any other game
Why don't you make like a tree and get out of here?