I've come from a highly competitive RP site where Mods, an equivalent of your RPJs, do have the power to declare characters dead or posts voided in case of a dispute or breaking of rules. Without their intervention people can kill off each other's characters (usually by using a stat system that the site relies on to make their attacks land). The picture is that staff holds a lot of power both OOC and IC, much more compared to what I see here. Also, since a small misstep can get your character killed even if you did not try to 1v10, even if you just forgot to add Private and No Kill tags on your thread while being in an area occupied by criminal characters. This results in characters dying often, no hit taking unless it can't be avoided, the fights lasting mere seconds during which everyone buff up to max and go for one shots and a lot of borderline metagame.
Compared to that, this picture here is really not that bad. Of course, as most things, this requires a level of... I lack the word here... awareness/consciousness. There will always be people to skim the edge of what the rules allow, poke the surface. On this site it appears simply talking to people can solve most issues and involvement of RPJs can solve nearly all the rest. I really love it how the characters can only be killed by the writer, because it allows to play the characters without worrying about some random killing them because they felt like it, it allows to play their story instead of fighting for their survival. I certainly don't think you should sacrifice that for a few abusers now and then, when they can be dealt with by so many other ways you guys have already explained. I have run into people who simply don't take a hit, I am yet to meet someone who would think he's invincible. Then again, I am not all that long here and I have my own RP habits from the other site, so not entirely without faults either.