The only reason someone would think having a shuriken as an item in a Zelda game would be a "good idea", is because they suffer something I like to refer to as the "crossover complex".
This is when a person has a strong interest or obsession over two different things, such as japanese weaponry, and Zelda thinks for one reason or another that it would be a logical idea to combine the two. Occasionally this emotion driven conclusion can conflict with the opinions of those who are only a fan of one of those things, and have no interest or opinion of the other.
Those that are only a fan of Zelda, and not of japanese weaponry, do not see it as a suitable Zelda item because of the pattern of previous Zelda games, and lack of any form of interest or opinion in japanese weaponry allows them to think about in a less emotional and more rational manner.
Additional information:
Returning boomerangs were origionally thought to be magical in nature, and boomerangs have an origin in many different cultures
Aztecs brought the ocarina to Europe, and went on to become popular in European communities as a toy instrument.
You do know that that was just a mention to the control scheme, right? (When TP was still in GC.) Phantom Hourglass is a normal Legend of Zelda game except the controls and it is coming out after TP.
Thank You!