Because one Pokémon-themed pirate of The Smurfs' Nightmare just wasn't enough.
Level Skip#
Press Left, Up, Down, Down, Right, Up, Left at the title screen. A sound will confirm correct entry. Start the game and press Select to skip levels.
While the above is identical to The Smurfs' Nightmare, in this game using the level skip will cause the music to stop until you complete the game or return to the title screen.