Yes I know. It acts like a fuel not an accelerate. Well unless we are talking torches. I just dont know how to explain it simply is all. To be honest I do not know the chemical reasons why oxygen is needed for fire to burn, I just know it does. I should look that up and learn something. I would guess that the molecules are broken down along with the wood / gas ect and continues the reaction (like combining fuels).
I just figured saying it "acts sort of like" an accelerant was the simplest way to put it. +1 for you.
It's not a fuel. You cannot ignite it. You meed fuel in an oxygenated atmosphere to burn. Remember the movie backdraft? Nevermind.
Burning is the rapid oxidation of a fuel source. The addition of heat and oxygen allows complex carbon and hydrogen chain compounds to break down to produce carbon dioxide and dihydrogen monoxide. This is why most fire suppression systems work on a smothering principle. You saturate the area with something that prevents oxygen from getting to the fuel and cools the area to prevent reignition.
Of course I'm generalizing from a single example here, but everyone does that. At least I do.