It weighs the exact same as a box of 12 Wood matches (and has the same +5% fire start chance bonus), and has unlimited uses.

Seems pretty useful to me.  Especially on Interloper, where there's barely any matches at all.

You want a useless item, Water purification tablets. Potable water is extremely easy to mass produce, especially if you've found a cooking stove; which can produce up to 12L of water every 2 hours.

Since the tablets come in packs of 4, you can only purify 4 L of Unsafe water, which will save you a single hour of boil time on two slots in that situation. And now those pots aren't syncronised with the rest of the pots!

The only place you'll maybe see them used a lot is in speedrunning challanges (particularly Whiteout), where you need to build up a stockpile of the stuff in the absolute fastest time possible.