Oh I can wholeheartedly relate to that, was an Energy Elf aka "def/attack buff and heal" sub class of Elf in Mu Global.
Loot share was a bitch, since I obviously stood at the center with mobs spawn at edges or at the back fighting a level boss, missing a drop being behind loot zone was common.
Plenty of times people thought nobody would notice in a log where gained exp or picked loot was displayed in details if item was picked up, there was a visible "item picked up by nickname".
So after a grind or immediately after a valuable gem dropped, people would bail or pretend it wasn't them.
Energy Elfs grouped up on forums, sharing nicknames and screenshots as proof of people with ill intentions or not be trusted.
This allowed to situations when Energy Elf could form a party with a one or few of those people, lead them to normally lethal area without a buff and if party decided to go AFK (which was common) feed them to mobs. Dieing cost exp drop or even their own worn equipment to drop
Don't piss off a healer.