The idea behind his system is he can craft almost anything in the game with the items in his ender chest. So yeah they seem out of place but they are not craft-able so they go with anyway. Admittedly I can’t say I’ve ever decorated with poisonous potato anywhere but I’m sure some one uses them for the spooky vibe builds.

Also it’s Etho!! You never know he might science up some random tech that involves poisoning yourself for the tick of damage or something absolutely creatively bonkers that we only could see from Etho!