You can not be snowbound all winter long. That is called an iceage. You can restock almost on a daily basis. I wonder how Eskimos survive for weeks above the tree line. Yes they do, look it up. Once again, stupid experts.
Eskimos have adapted to their environment over a dozen or so millenia. They also are equipped now with the latest modern conviences such as snowmobiles and firearms. The folks in Montana had no such conviences. As far as not being snowbound, coldbound or icebound, Montana is not Texas and in spite of the aura of "individual ruggedness" you can't win against elements such as four to five hours of available sunlight, extreme cold (average negative temperatures), frequent blizzards and cold fronts, not to mention such things as wild animals that were a constant threat because it's their element (and they're hungry too). The only way to win is to put the work in before winter (like the real pioneers of 1880) or you end up dying.
People who disparage historians, who have done their research and collected and analyzed thousands of data points, are full of hubris and arrogance and offer nothing to any discussion.
Finally, here's a link to the
experts. I'm sure they'd love to engage you with a debate on their stupidity.