Thought exercise for downvoters:

Imagine a section of your city which has been dominated for years by several gangs who have made a fortune in selling dangerous toxic drugs. They have further maintained their control of their territory by acts of violence and murder.

The widespread use of these toxic drugs have now devastated the physical and social environment, and lately it has become understood that the damage is far more pervasive and accumulative than was first realized.

Now at last powerful forces across the spectrum of society are pulling together to shut down the gangs' supply of toxic drugs. But new gangs in other impoverished neighborhoods are just starting to generate wealth selling the same toxic drugs.

They are defending against the Citywide initiative by saying it is unfair that they are being halted in their generation of wealth, and that because the devastation was started by the older gangs, they should be allowed to keep selling their drugs until they attain equity.

What is wrong with this argument?