"When using a bow, a character can draw ammunition as a free action;"
"Although they are thrown weapons, shuriken are treated as ammunition for the purposes of drawing them,"
and
[Quick Draw]. You can draw a weapon as a free action instead of as a move action. You can draw a hidden weapon (see the Sleight of Hand skill) as a move action."
Shuriken essentially have Quick Draw built into them; the feat doesn't help at all, except perhaps for drawing hidden shuriken.
