Some people are more adapted to the cold than others, but everyone needs protection from extreme winter weather. Everyone's teeth will chatter. Everyone's muscles will shiver. The body fights to keep itself and its inner organs warm enough to function.
This isn't possible without some sort of layering. Temperatures reach below 30 degrees Fahrenheit in various regions throughout the world. Plastic tents do not provide enough protection from the cold. That's why Zakat Foundation of America distributed winter blankets to Syrian Refugees in the Shuhada Camp near Idlib. The only way to survive the below-freezing-point temperatures of winter is to keep warm.
