Those problems are bureaucratic problems that will be solved with the money at stake. You're already protected with valet parking, through a combination of your

Those problems are bureaucratic problems that will be solved with the money at stake. You're already protected with valet parking, through a combination of your own insurance and the valets. This wouldn't be any different, you'd pay a few more bucks per year in insurance to save a large percentage in parking -- it would make economic sense in densely packed cities.