Does it make sense to carry a gallon or two of gas with us in the back of the SUV in case there is snow and traffic in one of these remote destinations? Or is that too dangerous in case there is a rear end collision?
There is no need to do so with a little common sense and other than the possible danger of doing so, one little spill and the car will smell of fumes.

It will be worth doing some homework with regards to lodging over the Christmas/New year period. You can check out options in the areas you wish to stay by using the RTA lodging link.