Charles Miller

Chosen answer: Evil Dead II starts out with a recap of The Evil Dead where Ash cuts off the head of his girlfriend Linda with a shovel and then is attacked by the entity, which is how the first film ended. While Linda is played by a different actress, it's still meant to be the same events as The Evil Dead. The cabin windows are still barricaded from the end of the first Evil Dead, and Ash's pant leg is still torn from Deadite Scott attacking Ash. Additionally, the end credits say: "Evil Dead II", the sequel to the ultimate experience in grueling horror, was filmed in Wadesboro, North Carolina and Detroit, U.S.A.

Bishop73

Chosen answer: If they had put an "Out of Order" sign, or left it unilluminated, someone in charge might try to have it fixed or replaced, or could have checked to see if it's plugged in, etc. By leaving it illuminated, it doesn't look out of place and simply not taking money wouldn't arouse too much suspicion. In my own life, when I've come across a seemingly working vending machine that won't take my money or dispense drinks (but gives my money back), I just find another one instead of calling someone or reporting it. But yes, it is very convenient to the plot that Mulder just happens to try and use this particular machine.