For the price of one of these drones they could ship 1000's of packages via the Post Office. One drone, one shipment. Ya, that makes a whole bunch of sense.
I'll be waiting for one to "fall" out of the sky, then demand a reward for it's return. Otherwise... in the trash (my hobby room) for "refurbishing" it goes. In Seattle, the Class B airspace extends from SeaTac out to 15 miles (30 miles across) and goes to 10,000 feet AGL. Mode C transponder and radio required, as well as a clearance to enter it in the first place.
First collision with another aircraft will bring so many lawyers out of the woodwork, I doubt even Amazon could survive the results.