I don't know the exact year that such regs went into effect. I think the rules come down to the principal... public land that's designated for hunting and other outdoors useis for the general public and not for individuals to carve out their own areas for their exclusive use. It seems like just common sense that we shouldn't go into our neighbors land and build something sem-permanent and expect to have exclusive use of. That's pretty much what people who build things on public lands are doing.
As I always say...