easy access. i frequently modify my kits as discovery and finances allow better components, so a sealed container wouldn't make much sense. i do, however, use water-tight containers wherever practical, even if that just means i put the gear in a ziplock bag before putting it in the kit. And i don't use the stuff in my kits for daily tasks; that's what my EDC is for.
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Camping teaches us what things we can live without.
...Shopping appeals to the soul of the hunter-gatherer.