I really don't see a problem here at all.

It's a dual use piece of equipment. Rather brilliant really. The Myo provides illumination and it's also a backup to matches or a lighter. Perhaps it could even be a primary source of fire. I'll bet it even heats up when wet.

But seriously........I wonder why only rechargeables cause a problem. I would assume they're referring mainly to NiMh chemistry. Possibly because the lower internal resistance of that design results in a higher current flow? It's not a voltage issue because Nicads and NiMh's have a lower voltage than non-rechargeable Alkalines or Lithiums.