Quote Originally Posted by slowthestone
A better question is...being as water is comprised of two highly flammable substances...why doesn't it flame cause it to ignite?
Oxygen is not flammable. And the answer to your question is that same as the answer to why NaCl is made of two poisonous elements, yet we put it on food.

I would also like to point out that steam burns are often made worse because they can pass through clothing with relative ease. More easily than boiling water can.