There's also one other thing that a physical TV remote has that TV back buttons or remote apps don't: tiny dots on/near some of the buttons. Most of the time, you can see this bump on the number 5 ...

Either way, these buttons are big business for the industry. Roku reportedly makes $1 per shortcut button on each TV remote. So we’re not expecting this trend to disappear anytime soon.

But, while Amazon's remote still has four third-party (non-reprogrammable) app buttons, rivals like Google TV and Android TV still let you reprogram their remote buttons, as noted by 9to5Google.