That stood out to me so much too and the way Fred was sitting. But also I think Bernie was interviewed in a restaurant so it reminded me of his segments too.
Bill is totally Glenn, but has Randy/Timothy's high voice. It really was spooky seeing Bill as the older Clark as he looked so much like older Glenn. I also saw in this interview where Fred & Bill were talking about how they came up with the Blue Jean Committee and this episode and Bill said even though he not an Eagles fan like Fred is he admired how Glenn was able to go out and do what he wanted to do based off Glenn's story in "HOTE" and going to that Beatles concert. But he did say too he based Clark off of Don too and the part about how it's lonely & windy on the top and seeing Clark's house.