Oh it is just those crazy witches up to their weirdness again...always so dramatic! Well, actually, yes, but they weren't just brewing up any old potion, they were also foreshadowing a new change in the mechanics of magic on the horizon...the use of focuses instead of a zillion little bits of material components. Call it the witch's alternative to the sorcerer's free eschew materials feat. Overpowered already you cry?! Well that ship has sailed, with a sea witch on it so best you just introduce more witch hunters into your campaign and move on.
So this would involve a new crafting category of "focuses" that would treat all material arcane (witch) spell components as needing just a focus instead...break out your charm bracelets and massive key chains...that would have a price of 1gp per spell level and dc of 10+ spell level to craft for calculating difficulty and materials needed. Crafting these on a log out in your swamp of doom? Well don't worry, your patron is looking over your shoulder as usual and will transmute any gems or precious metals into the necessary (items of value) you need along with a stick, rock, bone, old spoon or whatever you have laying around the shack as long as you have (gems or cp, sp, gp, pp) to offer up...the Axiomites are off the hook this time (see my thread on crafting magic items).
Sundering focuses, stealing them, etc.? Well that certainly is a possibility and there is plenty of lore about the willful teen that stole a witch's power by snatching their favorite bauble (read:focus), so, but expect them to be back in a few after a bit of a crafting flurry..prehensile hair/beard whipping about with vengeance!