What kind of fig? And perhaps everyone else knows, but what zone?
I have grown a Brown Turkey fig here for the past 7 years. So far I have brought it inside my sunroom to overwinter. DigitS pretty much described the way I've read to protect a fig tree over the winter in a borderline hardy zone. It did involve cutting one side's roots and trenching it under soil and mulch then cutting the other side to repeat the next year. Actually sounds like a lot less work that hauling it in and out. Now I have a 18X24' garden shed where I hope to keep it. I figure it should provide at least one zone warmer than outside.
It is not the snow that kills fig trees, it is the cold, the wind, and the quick changes in temperature. Until the tree gets bigger, you should try wrapping it with hardware cloth and fill the interior space with shredded leaves or straw then cover the whole thing with burlap. That will keep the tree warmer and protected from the wind and quick temperature fluctuations. Another way might be to stack hay bales around it, cover the bales with wood slats and add more bales over that. Breathing space and protection from wind and temp.
Also, one product soLucky mentioned goes by the name "Wilt Pruf". I use it to protect my rhodies from winter winds and it works well to protect those tender buds. I would certainly consider using it over the fig tree for extra protection. It must be put on after growth is over for the year and when the air temperature is above freezing (about 50s) so it has ample time to dry or it will do more harm than good.