Builder, after due consideration I can think of only two reasons California does not require orange on public land.

Either;

(1) the uber liberals in Sacramento are hoping to increase the odds that one of those dirty Bambi killing monsters who hunt will shoot another dirty Bambi killing monster instead of a cute innocent animal,

or

(2) it's so unlikely the few people in California who hunt (I think there are nine) will ever be in the same area at the same time that orange just isn't necessary.