Here’s how I understand it to work.
They have random periods of activity in which they advance as a species so they make large leaps in scientific progress when they are awake as opposed to a slow and steady build up of knowledge. Their large leaps in advancements becomes a disadvantage at times but more so their way of thinking in general.
Because they kinda portray themselves as humanoid that’s how you’re lead to think about them, like approximately human sized smart mamal-ish creatures, when really they are between ant to beetle sized hive mind creatures. This is why the more of them that they are able to have active between the harsh sun cycles the faster they advance. Also makes the whole dehydration thing easier to swallow.
I’d assume it’s for wood if there are designated fire areas for each camp. I could see it being even more useful for wet wood, allowing you to set it near the fire to dry out.