Get ready to have your mind blown, but the reason why Daniel Stern and Joe Pesci did not reprise their roles as Harry and Marv for Home Alone 3 was because of the unsafe working conditions of the film set. Those stunts were all real, and the two actors only agreed to star in the film if they were paid a large amount of money for their troubles.
Remember this scene? Daniel Stern was not told that he was going to step on a nail. Instead, he was informed he would step on a sharp tack. His scream was authentic because he actually impaled his foot on the nail.
Or this scene where Joe Pesci opens the door to receive 7th degree burns on his scalp. To obtain the surprised look on his face, director Chris Columbus told him a funny joke before he turned the camera on. Then, Columbus just pulled the trigger to burn Joe Pesci.
While the two actors would be hit in the face with paint cans, smashed in the head with an Iron, and burned with a scalding hot door handle; Daniel Stern and Joe Pesci reportedly “were fine” with the entire experience. (Being paid a lot of money helped them out too!)
In the sequel, Daniel Stern was actually electrocuted with 300 Volts of Electricity, and the cameras captured his authentic reaction to the shock.
Joe Pesci was actually exploded in the scene where his head is on fire and he dumps his head into kerosine.
Sure, this could have all been special effects, fake tools, props, and trick editing to look more painful than it really was, but what is this, a movie?