Right, and lighting a cigarette with a $1 convenience store butane lighter can be described innocuously as:

  Intentional ignition of an incendiary device via the combustion
  of highly compressed explosive gas using a manually triggered
  high voltage electrical discharge.

Edit: while you're technically correct that if what was made was designed to explode then it is an IED, you could also say that blowing air into a Ziploc bag, sealing it, and then stomping on it is also an IED. Are Ziploc bags designed for this use? No, thus it was improvised. Did it explode? Yes. Was it a device? Yes. The problem is that IED is such a loaded term and its use in this case can be quite misleading.