A game of hypocrisy. The other brothels and yours are being put out of business by this new one, which is supposedly wrong and unfair, and yet we're now attempting to do the same thing by taking over not only this new one but the others as well. Exactly the same thing.
By the description, this red-light district have multiple brothels, each catering to specific fetishes with each races running their own business. This mean the competitions does not step on each other's toe, since they all have something the others don't.
The new brothel run by the reincarnator though uses cheat abilities to steal everyone's customers.
We on the other hand are trying to unite the other brothels in a mutually beneficial relationship and join together into one "brand" as to have a chance at all to compete with the new brothel.
TL;DR: Imagine a foreign supermarket drop down in the neighborhood, and all the mom & pop local businesses need to form a local market to not get bankrupted.