No need IMO
Possibly, but it would not do any harm and might be the difference between success and failure.
You may not be aware that the boxes are a) smaller than Nationals and b) the boxes are of somewhat more lightweight construction than those of the National pattern. One can expect the lifts to ameliorate any direct wind effects on the boxes, but the insulation value of the outer lifts can be reduced considerably by small draughts.
Your opinion would deviate from mine in that the food required for the colony is partly proportional to the winter temperatures and, with that smaller box size, any reduction in stores required is a bonus towards getting a colony through the winter and added insulation for small colonies is not a bad thing to arrange.
It is so cost effective simply in stores used. I always draped old towels/hessian or similar over the inner boxes when I ran WBCs.
Some used to fill the lifts with straw chaff in days gone by - they knew the benefits of extra insulation back then. There are easier and more convenient ways to achieve the same result these days. I believe that every extra bee that gets through the winter helps the spring expansion. Perhaps some do not think that way.
