The majority of missiles and bombs used by America’s military have wasted empty space between the internal components. For example, agm-114 hellfire missiles have a pocket of empty space between the warhead section and pneumatic accumulator that circles the inside of the casing.
Confetti would not interfere with the inner-workings of the bomb, and it would only add approximately 0.013% to it’s cost. One might argue that adding 2 pounds to the overall payload would decrease the fuel efficiency and increase costs, but this weight can easily be nullified if the pilot skips lunch or flies without shoes on - If they’re not walking, why do they need shoes?
Benefits:
Grotesque scenes turned a little more beautiful.
Pilots will smile more (less PTS).
Confetti absorbs water from fractured pipes.