Worth carrying, and worth understanding, because the gap between what people assume it does and what it does is the single most consequential misunderstanding in camp hygiene.
Alcohol gel does not work against norovirus. The NHS is blunt about this: hand sanitisers “will not protect you against Norovirus”, and during outbreaks the instruction is to wash hands rather than use gel. Norovirus is the classic campsite, festival and shared-facilities illness, it takes a very small dose to infect, and it is exactly the scenario where a bottle of gel feels like enough and is not.
It does not deal well with dirt or grease either. Alcohol works on a visibly clean hand and does very little on a hand that has been handling firewood.
So the honest positioning is: gel is a supplement to washing, never the system. If your plan for hand hygiene is a bottle of gel, you do not have a plan, and what you need is soap and a way to use it.
Where it genuinely earns its place is the gap between activities when your hands are already clean: after handling a phone or money, before eating something with your fingers, when the washing kit is packed away. Buy 70% alcohol; weaker is less effective and the fragranced ones transfer their smell to food.
Handling flour counts as needing a wash rather than a gel, for the same reason: raw flour.