With many modern stoves incorporating Piezo igntion, it is easy to understand how people become reliant on these as the only means of lighting the gas. As some ultra-lightweight stoves forego these in favour of an external system, and to ensure it remains possible to light a stove in the event of Piezo failure, I choose to carry a small firesteel within my kit.
This ensures a spark every time, and means that I can always ignite a gas stove, and if necessary can start a fire using natural materials.
For the sake of a few grams, an item like this one could be a lifesaver.