They had to destroy the village in order to save it. After nine seasons and several TV movies worth of gentle homilies and pioneers building a civilized frontier, the residents of Walnut Grove blew up every building in town rather than knuckle under to the hostile railroad tycoon who had bought all the land. (Well, not every building. They spared the church and the Ingalls family house.) Maybe the writers were thinking Bridge on the River Kwai, but the result came out more Blazing Saddles.
Apparently, the nihilistic gesture was just a way for the producers to save some money. They were contractually obligated to the set’s landlords to leave the area as undeveloped as it had been before the show started. Producer/star Michael Landon conceived of the idea of destroying the set on camera as a pragmatic way of clearing the land. Plus, it meant no one else would ever be able to use the buildings for any other production. So, yeah, the act of vandalistic violence seemed to violate the show’s pioneer spirit and its implicit Christian principles — unless one of those principles is thrift.
[youtube=http://www.youtube.com/watch?v=XDymkPXrrTI]