Two things. First, it was Bobby becoming a real character. He's generally just been an annoyance to Sally or Betty but this episode he became a real character. Second, remember what he said about the wall paper? It didn't line up or match (something like that). Symbolized that many parts of society were not in alignment. Bobby's reaction? To pick it apart. So I read it as Bobby's world is coming apart at the seams due to all the unaligned things happening in society in 1968.