This has given me a good giggle. Imagine hordes of suitcases trundling around the departure lounge on their own. I can't see them working in Heathrow, it's too crowded!
I value a suitcase for it's lightness. In these days of reduced luggage allowance, I don't want the weight of the "wrapper" to be a large percentage of my quota. Imagine how much weight the batteries and motors add. Of course, my wife wants one now.