Most of my Amazon packages have been adequately padded, especially for higher price items. The only items that have not had padding were not particularly breakable & were in their own packaging.
I do agree that you should complain to them about this - there is no excuse not to use padding when shipping electronics. My guess was that they backed off on the padding because they got complaints from environmentalists, but saving a little money on packing material is probably a motivator for them as well. Regardless, it's not a good reason for poor customer service.