They're most likely for the Cable Box. If you check the Watch TV activity on the web page there is a link to Modify behavior of Activity, Picture and Sound buttons. At the bottom of the next page below all the hard buttons you'll see custom LCD commands - those appear in the LCD screen when you're in that activity. All the button mappings can be customized from this screen, plus you can customize the picture and sound buttons from their respective tabs.

Each device also has the same type of customization which is activated using the Device button and choosing a device.

You need to explore all the options for both devices and activities.