.... or have already had good luck on drops (or wasted hours on end) and they don't want the hard work of sitting in front of the PC annulled by giving the others an easier way to get the same items.
"Yes, RNG is fabulous. I'd much rather spend a week doing the same thing over and over again since all other content isn't really that interesting"
Anyhow, someone mentioned 100% drop each time with RNG = /random on who gets the item. It's fine, but what could be the problem is the length of FFXIV dungeons. They can be stormed through, and with a 100% drop rate each time (no abnormal re-entry timers) you could deck out a full pt in a day.
Difficulty/length/timers/exclusivity of the items dropped . . . . not an easy job to put them all into balance.