[LorenPechtel]

Hiking poles are a matter of the trail and the state of your body. These days I always bring mine but in general they spend far more time in a hand than actually being used.

Flat terrain or gentle climbs, I find no value in poles. Steep climbs (basically anything that has or should have switchbacks, or anything with steps) my knees are happier with them but it's not that big a deal.

Descending--this is why I carry them. Even a pretty gentle descent is going to hurt my knees if I don't have my poles.

As for lighters--disposable lighters run on butane. Butane has a boiling point of 32F. Good luck using your lighter if it gets too cold! Also, the matches in my pack can be lit and dropped into tinder sheltered under other wood, a lighter can't be. My emergency gear contains a cylinder of matches, each match held in it's own hole so there's no possibility of them rubbing against each other. (No lighter, though--where I hike an emergency fire would be difficult, campfires are almost always prohibited.)