I'm sitting here in the urban wildland interface.. More rural, and only have 100 years or so of whitey. Birds fly and carry seed, I've adopted a list of plants that I will only kill. If invasives were gone here we would have plenty left! It's not all about you city folk.
I do get the point of once its established it could very well be better than nothing. In that case I'd vote phase out vrs scorched earth.