Aside from the obvious issue of durability (or lack thereof) that I would associate with such a device that only cost around $20, this could prove useful in some situations where you want to flush an enemy out of some bush and don't have any other irritant to do it. A wailing, piercing noise may persuade your enemy to either A) remove the device therefore exposing themselves, or B) move away from the device therefore exposing themselves. Either way hopefully provides you a better target to shoot at.
