Within limitation.
Gear: Firstly, nobody can Merc the highest tier monsters on their own. A lot of mercenaries will be using third party software. This is clearly demonstrated in numerous online videos. Technically, against ToS.
Job Points: Bots. If you have ever come across people selling Job Points, they are more than likely using automation to do so. You see it time and time again in the notorious CP camps... And lets face it, who's going to play the game to get
100~2100 job points for somebody else in one hit?
I can locate any of these groups yelling for the sale of Job Point, stand there and video capture them fighting for hours on end, repeating the same pattern all day long.
The whole thing stinks, with money going to dubious places, disrupting/breaking the mechanics of the game, and distributing the balance of play.