Why did the Batman Film Dancers Union let Gotham self-destruct?

The alliance of shadow fighters is mostly the "assassin's alliance" in the original work. Master Ninja (actually a mistranslation of the film, formerly known as Lars? Al. Gul) thinks that human beings are the root of corruption and wants to beautify the world and create their own justice. The cartoon is one of the powerful villains of the Lord, who is proficient in fighting skills. In the past 100 years, he has accumulated a lot of wealth, amazing strategies and many times of cooperation with other villains. There are not so many rules and regulations in the movie, which means that gotham city is a decaying city, a group of people who want to create a "better society" to eliminate "decay".