When Elsa is waiting in the lobby, she's wearing a dress which shows her normal, not wooden legs. It's very apparent when she is crying on the floor.
They pay homage to the original 1932 movie Freaks. In Freaks, Cleopatra gets mutilated and turned into a tarred and feathered bird for visitors to gawk at in terror. Hercules gets viciously attacked under the carnival vehicle. In this episode, Stanley gets cornered by all the freaks under the carnival vehicle and gets viciously attacked and mutilated to resemble Meep (a feathered freak who was killed by the cops in an earlier episode).