He was pointing out that people are like pickles, dull and all the same. They have a khaki personality. People in most modern cities value superficial things like being well dressed and all behaving the same and don't like people that match up to their status.
When I was a young boy, I thought the song was about bricks and concrete. I'm not sure why, perhaps because bricks are used in every city and made all the buildings look the same. They played that song often in the '90s.
