I know that amazon search was there also in 16.04 because it was my first distro and in my country i only briefly heard about amazon so it looked cool to me to have one button to order something but i never clicked on it because i tought it only works in rich countries or something. At that time i didnt gave a crap about privacy i was sold on it because i liked the design of unity and the fact that it looks different than school pcs with windows so it didnt remind me school