This happens every day when businesses are put into administration and immediately brought out of administration by their former management, or a suitor in what is called a "pre-pack administration". They are thoroughly unethical, and as you quite correctly say, leave suppliers out of pocket as the "new owners" rarely buy the liabilities, just the assets.
Distasteful though it is is, it is legal, and there is no reason why airlines shouldn't be resurrected in the same way. In my opinion, having been on the wrong end of a number of "pre packs" I would like to see the practise stopped across the board, and our response to a "phoenix business" looking to work with us was simple - "you're a cash account until such time as you settle the outstanding debt from the failed business". It was a win win policy, we either got positive cash flow by being paid up front, or the new business settled the old debt and resumed normal trading with us.