To be honest, thinking that the creatures burn like really dry gasoline-soaked tinder is incredibly risky, considering that there are no creatures alive that burn like that. To simply guess that they might burn like that and let these beasts come at them shows a soul who is incredibly... foolish, I would say.

Not even dry wood catches fire like gasoline. Not even really, really dry wood. I would know. We've had a drought here for over a decade.

And a lighter is kind of risky. Unless they're as oily as gasoline, you're dead. And you have to be REALLY damn close to use a lighter. And if they do burn like gasoline, you'll likely be burned from proximity.

It's really just a bad idea overall.

Just saying.