Seriously, I don't carry anything that I don't use, unless you include something like mittens which could make a huge difference if conditions turned nasty; mostly I don't use them, but occasionally I do.
I am forever examining my equipment list, and after my last multiple-day trip (September 2019) I decided to stop taking my plastic teaspoon, because I realised I only ever used it for spooning out instant coffee, which I can do just as well with my plastic dessert spoon. Then there was a little collapsible funnel that I used to aid filling my plastic water container; the plastic measuring beaker that I now use instead of a mug has a pouring spout that renders the funnel uneccesary.