Deliberate mistake: The signs at Dachau Concentration Camp are in English.
Deliberate mistake: The first of two twists meant to come at the end of this episode was the revelation that the mysterious dark rider chasing Anne was herself - 25 years in the future. According to writer Richard Matheson, the director chose, for some bizarre reason, to deliberately spoil this "reveal" by inserting a close-up of the rider early on, showing the viewers who she was at the outset.
Mr. Garrity and the Graves - S5-E32
Deliberate mistake: Garrity blackmails the town citizens into paying him not to resurrect their unlamented "loved ones." Amazingly, every man in the saloon just happens to have hundreds of dollars ($500 - $1200 each) in his pocket to pay up with. In 1890 money, that's roughly equivalent to a group of modern-day bar patrons all carrying ten to thirty thousand dollars around in their pockets. The scenario was apparently used in spite of its incredibility just to more quickly advance the plot.
Deliberate mistake: Sport's voice is noticeably dubbed by a different actor in several scenes throughout the episode. Her voice inside Aunt T's house is the original audio track done by the child actor. During the other scenes, the voice is done by June Foray (uncredited).
Answer: It's explained in the episode. The aliens are experimenting to see how humans react to various scenarios. This just happens to involve them using super strength.
Thanks. It's been a long time since I saw the episode so I forgot.