That show is not bad, but not my fave antiquing show. It has actually received some backlash, even from other dealers. Here is a funny video on Youtube spoofing the show:
I wouldn't quite call them swindlers, but the reason they must love to go to these farms is the farm owners probably don't realize the value of some of the stuff. Ironically the makers of the Youtube video post a link to buy "American Swindler" t-shirts at the end of their video so they are hardly ones to criticize.