It would be interesting to know what the rules are about pigs. I've seen Craigslist ads for natural pasture raised hogs in SE MN that looked very similar to the hogs we shot in Texas. They were openly advertising at one point, so I'm assuming it was legal to have some type of pasture raised hog that looked pretty wild. Their pictures showed these hogs running around a pasture that looks like it should hold beef cattle. If my memory is correct, I think the price per pound was extremely high for the type of heirloom breed they were selling.
I know that grass fed, free range, cage free and other similar descriptions seem to bring in higher prices for livestock so maybe pasture raised semi-wild hogs will be more common. I wish a had a neighbor that had heirloom hogs that occasionally escaped rather than the 2000 pound black angus steers that occasionally work their way into my food plots.