If you are required to have a second seat, it should be a fully operational racing seat, that matches the drivers seat. I think its funny to require a second seat, just for it to be a superlight unusable seat, and or covered up with aluminum.
I ran my passenger seat at the Elsinore round last year, and was surprised not to see many other passenger seats. Im fine either way, as long as its enforced. I personally would like to run it without, as my car is pig heavy, and my seat with mounts weights like 30 lbs!
Its not like they would ever let us race with a passenger. They were going to do that with the superlites, and someone got hurt the first race, so no passengers...