'House nut' is a term often used in the movie industry and is defined as the sum total of operating expenses for a given period of time. The word has it's origins in days when vaudeville performers would move from town to town, setting up their act for a few days then leaving. Many times they left in such a hurry that they never had a chance to pay their debts in town. Local sheriffs began to combat this problem by removing the nut connecting the vaudevillians' money cart/stand/wagon to their method of transportation, usually a horse or car. They were forced to pay their debts so that they could get the nut back from the sheriff. The term just kept up as movie theaters began to grow. In the early days, cinema was seen as just another entertainment performance in the vein of vaudeville shows so the same principle applied.