Personaly I think this is a very simplistic way to decide if something is evil or not. Besides that there are actions you can do in this game which are illegal. For instance sending your working girls to work on the streets (they can be arrested), letting your friends sell drugs in a drug den (again they can be arrested) or kidnapping girls to the farm and force them to sign a slave contract (at least in the original EVIL this can lead into a federal investication if those slaves are arrested on the streets).
Why i think it's simplistic. Simply because if a upper class (law makers) decides if some activities are illegal or not, it doesn't mean that the common people think exactly the same about those activities. In the case of this game it could be possible for example that the upper class is highly corrupted and only thinking about their own profits and social status which could be a reason for legal slave trade, while the common people consider this evil because they can fall victim to this.
Not saying that the backstory doesn't need changes. But things in life aren't black and/or white. There's a whole area of shades of grey in between.
