I'm not sure how you equate putting stakes in the ground with building a snow cave (which frankly would be a stupid idea given how critical warmth would be to Luke survival).
Re-read what I said. Han's putting up stakes suggests him NOT building a snow-cave, as suggested by the Mythbusters during their test. And while in the "tauntaun" Luke continued to lose body heat, not gain it. My question is one of whether it was necessary, if putting Luke in tauntaun even helped. I guess a "control" is what I'm talking about.
Snow caves, also, are pretty critical to build in dire situations as they can provide "warmth" (or at least trap warmth radiating from your body while inside it.) It's a survival technique people do use in extreme circumstances.