We have tons of Amish around here, I think the aspect of dues and an internal organization running their insurance is probably true and the basis for this show. Also you can make good money being an Amish taxi driver, some people's entire career is doing just that. Most of the Amish I've ran across are genuine good people which is rare anymore. The only run ins with the law you hear about are sex abuse/child abuse and sometimes DCS has to get involved with them but that's extremely rare.
Random fact, my friends girlfriend went to pass some Amish people on a buggy and ran into them just like they were saying in the show. She flipped her little Ford SUV a bunch of times and got a big cut on her foot. Amish kid got his leg broken and it destroyed their buggy.