Hobgoblins was actually offered to MST3K by director Rick Sloane.
When Amy says, "I want you to treat me like dirt," Tom says "Like Phil Dirt?" This is an allusion to the legendary disc jockey who played surf music on KFJC radio in California.
When Dennis opens the vault, Mike says "Burgess Meredith's in there reading." This is an allusion to The Twilight Zone episode "Time Enough at Last", in which he played the bank teller who just wanted to read.
When the Hobgoblins take the golf cart, Crow says, "What have they done with Casey Martin?" He is a professional golfer who sued for the right to use a golf cart in tournaments because he has a circulatory problem in his legs.
Tom Servo appears with a leather jacket, sunglasses, and gun. He goes through a time machine, in an attempt to stop the director the film from making "Hobgoblins" (which he fails at). This is a reference to the "Terminator" films, where Arnold Schwarzenegger has a leather jacket, sunglasses, and gun, and goes back in time to prevent numerous things throughout the films.