When did high design become synonymous with luxury? The question kept surfacing in my mind as I walked the thousands of steps of Milan Design Week, my iPhone keeping track of the calories I was shedding along the way (theoretically, elevated pasta intake excluded). Getting steps in is a point of pride for many, especially when it comes to Milan, where you are constantly on the move — except for when you find yourself in an interminably long line to get into some palazzo, or even one of the more popular halls at the fair itself. All of this energy is going toward experiencing design in all of its permutations. But one of those variations was more pronounced than others: big luxury. 

What is luxury? It has different meanings for...