The bad stereotype of rustication is that it is first of all cheap, and second, just a way to cover up badly flawed and probably inexpensive briar. I'd say that is perhaps twenty-five percent of the story, not true about most rusticated pipes. Lesser, more imperfect briar may get routed to the factory line that is doing rusticated pipes, but those lines probably end up using some briar that would do fine as smooth or blast finishes -- i would propose, knowing the time constraints of most factory operations.
Having said that, I'd note that rustication runs the gambit from fairly primitive carving and texturing to some able crafted dappled surfaces that are as handsome as most sandblast, to some high artistry in rustication that is elevated to skill and artistry of its own. To talk about rustication as one thing means you're not looking a the pipes very well.
Many high end brands and artisan pipes use rustication, and some of it is masterful. And there are cheap and miserable examples of smooth and sandblast finishes. So look carefully, and fully see what you are looking at. You don't have to like rustication, and you sure don't have to buy it. But think about what you are seeing.