It is true it would be more fun to culture them. Unfortunately they don't like to be seen, are rather small, and as you said are cannibalistic so they don't make very good display animals. If it weren't for these flaws I am sure they would be very interesting to culture in a zoo. It is a shame that the Saint Helena earwig (Labidura herculeana)is extinct because then I think people would be more open to keeping/seeing them in insectariums. I might try to keep some at my apartment in culture though because they are such cool animals. Thanks for the idea.
And while I am wishing for animals to be so much larger than their actual size Psudoscorpions would be so cool if they were about 100x their actual size. I do culture those in my personal collection.