Building disadvantage and safety from mobs, staff shouldn't be able to use it for non staff uses as it's abuse and an unfair advantage over the rest of the users
Being able to build with fly isn't a disadvantage to you, as you aren't competing for anything. The ability to fly in survival mode doesn't affect you as a player in any way.
Being safe from monsters is something anyone can do, by lighting up the ground they're working on. That's hardly a disadvantage to you, nor does it affect your gameplay in any way.
You said this is abusive, however it's not abusive. We gave moderators fly so that they can fly. How they choose to use fly is up to them. They can't possibly abuse it because we never told them how they can or cannot use it. It's not something they need, it's a perk we let them have. There is no "staff use" for fly, unless you're an Admin in which case you need to be able to fly to effectively use worldedit.
This isn't really a staff report, this is more of a suggestion to remove fly from our moderators. If you wish to make a suggestion, please place it in the proper forum category or add it to the #suggestions channel in our Discord server.