I'd give some of these people the benefit of the doubt. Sometimes things happen where you ready a weapon skill and someone else gets a weapon skill away under yours and you end up with a ruby kill. However, you wouldn't be wrong in calling out the egomaniacs who recklessly rack up ruby lights with no consideration for time when there are not enough targets for Black Mages to offset them with azure lights, which can be done in La Theine, Attohwa, and Ulegurand.
In any case, it would help if people stop treating Abyssea parties as if some kinds of online trophies are being given out a la Halo or some other copycat game played by ADHD teens with no real accomplishments to speak of. You're not the only heroes in this world.