Us old timers remember what was happening at the time. It turns out it was an incredible deal for both sides.
The 1-click patent didn't have a great deal of credibility at the time. Many people in the tech industry were railing against Amazon and 1-click. It seemed like such a stupid patent and I think a lot of people didn't expect it to hold up.
Apple launched the iTunes store with $0.99 mp3's during the same period and the whole thing hinged on 1-click shopping. You could click a button to preview and there was one right next to it that would buy the song. No confirmation screens or checkout process. Downloaded and added to your library. It was so easy and people were spending a fortune on there because there was nothing else like it. Keep in mind this is one the heels of the decline of Napster and other mainstream P2P apps. People were being ratted out by their ISPs, sued and settling for $3000 for downloading some crummy song. Here you could do it legally and inexpensively and with a great UX because of 1-click. And for the first time you could buy a single song instead of an entire album. Prior to that, we had "singles" that contained a radio song from the album and a couple b-sides for like $5-8.
Apple had to launch iTunes with 1-click for it to be successful. The $1M license fee cost far less than the inevitable lawsuit would have. They made a fortune with iTunes and used it to enter new product categories. You could argue that that was one of the pivotal moments that transformed the company into what it is today. That licensing fee was highway robbery.
You also have Amazon who, at the time, had an outstanding selection, the best prices, fast handling times, reliable shipping and the most friction free buying process anywhere. Many retail sites didn't even have user accounts back then. You would enter your info with each order. The ones that did have accounts still made you click through several screens to place an order.
Amazon's end of the deal is they got paid $1M to not have to sue anyone (and possible lose) and have their ridiculous patent become credible overnight. The result was they maintained their superior online shopping experience by preventing others from mimicking it and leveraged it to become the beast they are today.