Northern Dancer
Survivalist
A primitive but a useful immediate shelter if one has to use one.
And then again the modern camper can do something like this...
What ever you do think about the environmental impact and do what is best for the immediate situation. When you are finished break it all down and leave no trace.
In many parks you can find something like this -
That can be mighty fine on a rainy cold day. I've used them in the winter and was surprised how warm they can be.
There are a lot of choices for shelter these days - primitive and modern.