It's the NRL's competition.
You're absolutely right and that is the problem. Sixteen clubs, soon to be seventeen, co-operate with one another in a competition for their mutual benefit. The vehicle that they use to facillititate that competition, the NRL, has taken total control and can hold any or all clubs to ransom.
Twenty years ago the NRL, which at the time had assets worth millions, threw out South Sydney, a founder member. If they had got away with it, Souths, who over the years had contributed enormously to the accumulation of those assets, would have been out the door with nothing. Fortunately the courts ruled that the NRL could not do this, and Souths were reinstated. The NRL has since changed its administrative approach so that each new season, all of the clubs must apply for admission to the competition for that season. If the league want to get rid of a club they can now simply decline to accept the entry of that club. If, or should I say when, this happens, we shall be back in court again, possibly with a different outcome to the Souths case.