What is the advantage to using images instead of actual radio inputs

Question

What advantage could there be for Amazon to use images of radio inputs as opposed to actual <input type="radio" />? Is this a browser compatibility solution perhaps?

I have never seen <input type="image"... /> either (second line of the code). How can an image be an input?

And I threw in the javascript tag because that's what's being used to update their state.

Answer 1

The use of an image is purely for style consistency sake, as styling an input is very hard to maintain cross-browser.

Also, this particular input is not an exact replacement for a radio button, but rather Amazon is using a image submit button to gather what the user has selected. Likely, once you click on one of these options, a form is submitted or another function is triggered.

Answer 2

They use images because they know exactly how it will render on all browsers, and there is virtually zero discrepancy.