So today I finished Dead Money and I was thinking about the Ghosts the whole time. We already know most of the stuff in Dead Money comes from Big MT. Well, the Hazmat suit is what the Ghosts wear. What if Sinclair had a bunch of the Hazmat suits for everyone in the Sierra Madre for when the bombs fell? Maybe these suits had Y-17 Trauma Harness technology in them that he didn't know about. It would explain the lack of bodies in the Villa, I mean there aren't very many for the grand opening of a casino. PLUS, the Ghosts won't stay dead unless you cut off a body part. And what was the main purpose of the Y-17's? To make people who were injured or suffering from exhaustion get back to somewhere safe. Maybe they are like the ones in Big MT., protecting their area.