Much of the underlying technology involved is hidden from the public and the competition, but they could emulate and simulate to provide similar results if they so wished. In many cases they already do this, or come close to it.

In one example[0], an online retailer was taken to court by Amazon for using a one-click buy button. Having all of the customer's billing and shipping information on hand already, this feature is obvious and makes sense for any online retailer, but Amazon has patented it. The competing retailer's solution was to add a confirmation page, increasing it to two clicks but providing similar convenience.

[0]: http://en.wikipedia.org/wiki/1-Click#Barnes_.26_Noble

Edit: Added a link to the referenced case