It could be a carry over from yesteryear when winter tires were put on the rear only, to facilitate traction with rear wheel drive. It was also more convenient to have the extra wheels ready to put on when actually needed, than go to a tire changer, many miles away, on short notice. Back then, steel wheels were the norm year round.I've read the only difference would be price, winter wheels are cheaper. Some also supposedly have an extra chemical resistant coat.
Being in Canada, I suppose winters are long. Why you want nice wheels on a short sunmer but ugly wheels during the long winter?
FWD and the need to dress up mostly mundane looking vehicles these days, has lead to the fancy wheels. I don't know that that is debatable. Look at those 1957 Ford Fairlanes.