[Bacardi]

what you get m_hEffectEntity ?
or m_iParentAttachment

*edit
maybe those not have purpose

[Halt]

Perhaps hooking "object_destroyed" and just killing entities there before they become different entities might be a work around?

[Powerlord]

Bear in mind that these entities are essentially ammo boxes, so just getting rid of them wholesale can have gameplay consequences, particularly for Engineer or Spy.