I've got my Awning, do I really need a Carpet and a Footprint Groundsheet to go with it?
You don't have to have either, however, both offer a great benefit to you.
Most Awnings these days have a sewn-in groundsheet, if it's been raining and it's wet ground when you come to pack up the awning, having a sewn-in groundsheet means that you can pack it away with the sewn-in groundsheet clean and dry, and just clean the footprint off separately. A Footprint Groundsheet will also give you extra insulation and provide protection from stones.
A Carpet for an awning might be considered a luxury item, but it really can add so much to your camping trip, especially if you are planning to, or the weather causes you to spend extended periods of time sitting in the awning. Put it down in the living area, it will be softer and warmer underfoot and provide a much homelier place to sit and relax than just sitting on the groundsheet.