11600AS$ is not really that little if you compare it to US$, for example I could buy a Dacia and use it as a "follow me" car at my terminal. Compared to my profits of 50,000,000AS$ it is not that much.
I mean from a logical point view, I absolutely share your opinion that for some flights it doesn't make any sense to allow cargo.
I still doubt, that the downside is actually 11.600. But even if that is the case, the time invested in identifying and changing affected routes probably is invested better in other cost saving or revenue driving options.
It's really a beauty kind of a feature. But having said this, I guess we will see this combined with other features.