There are some scenarios I wish were possible with compendiums: Being able to turn 1 or more of the compendium products off for a game. When I am making 5e adventures for the marketplace, I am not allowed to use anything outside of the SRD. I purchased the 5e PHB to share with my players, and I am always having to rename things in my games for the marketplace when dragging items from the compendium. Being able to turn off the PHB compendium for a game would make it much easier to not mess that up. Choose which compendiums to share. I would consider getting the 5e Monster Manual if I could turn it off and also ensure that it was not shared with the players in a game. Or some games might have options from Xanathar's but not another expansion book. Turn off categories of content. Some books have both player options and monsters. I would want to share the player options but not the monsters with the players.