Durham tuned the discussion out and turned to Ruby. “What exactly is the point of building a dungeon?” Some big underground maze full of traps and monsters. Seems like a lot of unnecessary expense and effort. And why are they called ‘dungeons’? I thought dungeons were places where prisoners were kept.” Ruby looked up with the spark in her eyes that Durham had come to realize appeared whenever a question was asked that fell anywhere near the history category. “Well, once you place prisoners somewhere, you place guards and locks there as well,” she said. “Eventually someone realized that they could save a bit of coin on guards by replacing them here and there with a few deathtraps in choice spots. Now you’ve got an underground place with locks, guards and traps — only natural for it to start looking like an ideal place to keep your valuables as well. Once you start keeping valuables down there, it makes a certain sort of sense to move the criminals elsewhere. Or to maybe just lop their heads off. The idea caught on well in Keine. They think whatever is buried with you goes with you beyond. They fill their tombs with treasure and virgins…” “Virgins?” Durham asked. “People virgins? Alive ones?” “Well, they don’t stay alive for too long once the tomb is sealed, but yes, people virgins. Well, maybe some other varieties of virgins too but that isn’t something they tend to advertise. Afterlives, regardless of their religion, tend to have a common theme in that they last a very long time. One needs to pass the time somehow and un-virgining virgins might seem a more appealing prospect than rereading all of your books again. You give them poison jewelry, light them on fire or wait a few weeks for them to starve to death. The notion is that if someone robs your tomb that you lose your treasure in the afterlife as well. But even if someone takes all of your gold it’s pretty good odds that they’ll leave you your virgins. Far lower resale value.
— The Dungeoneers (The Dungeoneers, #1) by Jeffery Russell (46%)
If you've ever wondered why dungeons in fantasy worlds are filled with treasure instead of prisoners, you've got your answer right here in this book.