It was probably from the 70s, I saw it on TV about 10 years ago. These 2 women are held hostage in their own home by 2 bikers while their husbands are out of town. The movie ends with the 4 actors in bed together when the husbands get home and shoot one of the bikers. Then everyone starts laughing and the crew walk into the shot and laugh with the actors while the credits roll.